Nabilone should be administered with caution to patients who are taking other psychoactive drugs or CNS depressants, including alcohol, barbiturates and narcotic analgesics, or to those with a history of psychiatric disorder (including manic-depressive illness and schizophrenia).


Drugs that reportedly may increase oral anticoagulant response, ie, increased prothrombin response, in man include:alcohol*;allopurinol;aminosalicylic acid;amiodarone;anabolic steroids;antibiotics;bromelains;chloral hydrate*;chlorpropamide;chymotrypsin;cimetidine;cinchophen;clofibrate;dextran;dextrothyroxine;diazoxide;dietary deficiencies;diflunisal;disulfiram;drugs affecting blood elements;ethacrynic acid;fenoprofen;glucagon;hepatotoxic drugs;ibuprofen;indomethacin;influenza virus vaccine;inhalation anesthetics;mefenamic acid;methyldopa;methylphenidate;metronidazole;miconazole;monoamine oxidase inhibitors;nalidixic acid;naproxen;oxolinic acid;oxyphenbutazone;pentoxifylline;phenylbutazone;phenyramidol;phenytoin;prolonged hot weather;prolonged narcotics;pyrazolones;quinidine;quinine;ranitidine*;salicylates;sulfinpyrazone;sulfonamides, long acting;sulindac;thyroid drugs;tolbutamide;triclofos sodium;trimethoprim/sulfamethoxazole;unreliable prothrombin time determinations;warfarin sodium overdosage.


Cyclosporine, Digoxin, Methotrexate Lodine, like other NSAIDs, through effects on renal prostaglandins, may cause changes in the elimination of these drugs leading to elevated serum levels of cyclosporine, digoxin, methotrexate, and increased toxicity.


Caution is therefore advised when administering PEGANONE to patients receiving coumarin anticoagulants.


Since bacteriostatic drugs may interfere with the bactericidal action of penicillin, it is advisable to avoid giving tetracyclines in conjunction with penicillin.


Morphine: Combination hormonal contraceptives may increase the clearance of morphine.


These studies indicate that ketoconazole or erythromycin co-administration enhances fexofenadine gastrointestinal absorption.


Warfarin: Quinolones, including enoxacin, decrease the clearance of R-warfarin, the less active isomer of racemic warfarin.


Oral Anticoagulants CAUTION SHOULD BE EXERCISED WHEN COUMARIN ANTICOAGULANTS ARE GIVEN IN CONJUNCTION WITH TRICOR.


The reduced risk of adverse events and therapeutic superiority compared with haloperidol and risperidone in the treatment of negative and depressive symptoms support the choice of olanzapine as a first-line option in the management of schizophrenia in the acute phase and for the maintenance of treatment response.


Pharmacodynamic Interactions: The CNS-depressant action of the benzodiazepine class of drugs may be potentiated by alcohol, narcotics, barbiturates, nonbarbiturate hypnotics, antianxiety agents, the phenothiazines, thioxanthene and butyrophenone classes of antipsychotic agents, monoamine oxidase inhibitors and the tricyclic antidepressants, and by other anticonvulsant drugs.

thioxanthene classes of antipsychotic agents


Although specific drug interaction studies have not been conducted with ALPHAGAN P, the possibility of an additive or potentiating effect with CNS depressants (alcohol, barbiturates, opiates, sedatives, or anesthetics) should be considered.


Multivalent Cation-Containing Products: Concurrent administration of a quinolone, including ciprofloxacin, with multivalent cation-containing products such as magnesium or aluminum antacids, sucralfate, VIDEX chewable/buffered tablets or pediatric powder, or products containing calcium, iron, or zinc may substantially decrease the absorption of ciprofloxacin, resulting in serum and urine levels considerably lower than desired.


However, concomitant administration of aspirin with CELEBREX may result in an increased rate of GI ulceration or other complications, compared to use of CELEBREX alone.


Presumably, phenytoin acts as a stimulator of coumarin metabolism and has been reported to cause decreased serum levels of the coumarin anticoagulants and increased prothrombin-proconvertin concentrations.


The lower rate of absorption in the groups receiving 446 mg Fe instead of 48 mg of Fe per kg diet resulted in a decreased renal excretion of cobalt.


Misonidazole reduced the antitumour activity of oral CCNU by dose modifying factors (DMF) of 0.58-0.71.


The actions of the benzodiazepines may be potentiated by barbiturates, narcotics, phenothiazines, monoamine oxidase inhibitors or other antidepressants.


Propranolol attenuated the heart rate increase following administration of immediate release nisoldipine.


Interaction on the antinociceptive effect between neurotensin and enkephalins or tuftsin.


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


Therefore, when chlorothiazide and non-steroidal anti-inflammatory agents are used concomitantly, the patient should be observed closely to determine if the desired effect of the diuretic is obtained


Acetazolamide decreases urinary excretion of amphetamine and may enhance the magnitude and duration of their effect.


Haloperidol reduced or eliminated the increases in FI responding produced by intermediate doses of either (+)-NANM or PCP in pigeons, but did not antagonize the decreases in FI or FR responding produced by high doses of PCP or either stereoisomer of NANM.


Sumatriptan: Sumatriptan has been reported to cause coronary artery vasospasm, and its effect could be additive with D.H.E. 45  (dihydroergotamine mesylate) Injection, USP.


Following oral administration of two 150-mg sustained-release tablets with and without 800 mg of cimetidine, the pharmacokinetics of bupropion and hydroxybupropion were unaffected.


Cholestyramine-Concomitant intake of cholestyramine and vitamin K may reduce the absorption of vitamin K.


Co-administration of bosentan decreased the plasma concentrations of glyburide by approximately 40%.


It is possible that the cardiovascular action of other calcium channel blockers could be enhanced by the addition of Nimotop .


Agents Causing Renin Release: The antihypertensive effect of enalapril and enalapril IV is augmented by antihypertensive agents that cause renin release (e.g., diuretics).


Dexbrompheniramine can interact with alcohol or other CNS depressants (may potentiate the CNS depressant effects of either these medications or antihistamines), anticholinergics or other medications with anticholinergic activity (anticholinergic effects may be potentiated when these medications are used concurrently with antihistamines), and monoamine oxidase (MAO) inhibitors (concurrent use with antihistamines may prolong and intensify the anticholinergic and CNS depressant effects of antihistamines).


While no in vivo drug-drug interaction studies were conducted between estazolam and inducers of CYP3A, compounds that are potent CYP3A inducers (such as carbamazepine, phenytoin, rifampin, and barbiturates) would be expected to decrease estazolam concentrations.


The hypotensive effect of sodium nitroprusside is augmented by that of most other hypotensive drugs, including ganglionic blocking agents, negative inotropic agents, and inhaled anesthetics.


Amitriptyline in combination with clonidine enhances the manifestation of corneal lesions in rats Epidural Injection Clonidine may potentiate the CNS-depressive effect of alcohol, barbiturates or other sedating drugs.


Multivitamins, or other products containing iron or zinc, antacids or sucralfate should not be administered concomitantly with, or within 2 hours of, the administration of norfloxacin, because they may interfere with absorption resulting in lower serum and urine levels of norfloxacin.


Care should be taken if labetalol is used concomitantly with calcium antagonists of the verapamil type.


A two-way interaction between the hydantoin antiepileptic, phenytoin, and the coumarin anticoagulants has been suggested.


Magnesium- and/or aluminum-containing antacids, products containing ferrous sulfate (iron), multivitamin preparations containing zinc or other metal cations, or Videx (didanosine) chewable/buffered tablets or the pediatric powder for oral solution should not be taken within 3 hours before or 2 hours after FACTIVE.


The most commonly occurring drug interactions are listed below: - Drugs that may increase plasma phenytoin concentrations include: acute alcohol intake, amiodarone, chboramphenicol, chlordiazepoxide, cimetidine, diazepam, dicumarol, disulfiram, estrogens, ethosuximide, fluoxetine, H2-antagonists, halothane, isoniazid, methylphenidate, phenothiazines, phenylbutazone, salicylates, succinimides, sulfonamides, tolbutamide, trazodone


Concomitant administration of Mefloquine and other related compounds (eg, quinine, quinidine and chloroquine) may produce electrocardiographic abnormalities and increase the risk of convulsions.


Paroxetine: Coadministration of a single dose of Sonata 20 mg and paroxetine 20 mg daily for 7 days did not produce any interaction on psychomotor performance.


Ketoconazole: When a single 125-mg dose of Aprepitant was administered on Day5 of a 10-day regimen of 400 mg/day of ketoconazole, a strong CYP3A4 inhibitor, the AUC of aprepitant increased approximately 5-fold and the mean terminal half-life of aprepitant increased approximately 3-fold.


Veratrum alkaloids: Amphetamines inhibit the hypotensive effect of veratrum alkaloids.


Insulin: A clinical study in 6 insulin-dependent diabetic patients demonstrated no effect of EXTRANEAL on insulin absorption from the peritoneal cavity or on insulins ability to control blood glucose when insulin was administered intraperitoneally with EXTRANEAL.


In patients receiving nonselective monoamine oxidase inhibitors (MAOIs) (e.g., selegiline hydrochloride) in combination with serotoninergic agents (e.g., fluoxetine, fluvoxamine, paroxetine, sertraline, venlafaxine), there have been reports of serious, sometimes fatal, reactions.


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


A 21 (17)% decrease in the steady-state AUC of ganciclovir was observed when VIDEX was administered 2 hours prior to ganciclovir, but not when the two drugs were administered simultaneously (n = 12).


Lithium generally should not be given with diuretics because they reduce its renal clearance and add a high risk of lithium toxicity.


Expected changes in laboratory assessments of PT and INR were observed after warfarin administration, but these changes were not affected by concomitant lenalidomide administration.


Adrenergic Agents:Some individuals receiving ZYVOX may experience a reversible enhancement of the pressor response to indirect-acting sympathomimetic agents, vasopressor or dopaminergic agents.


Tricyclic antidepressants may antagonize the hypotensive effects of clonidine.


If concomitant treatment with sumatriptan and an SSRI (e.g., fluoxetine, fluvoxamine, paroxetine, sertraline, citalopram, escitalopram) is clinically warranted, appropriate observation of the patient is advised.


Co-administration of CYP3A4 inhibitors (eg, ketoconazole, itraconazole, erythromycin, grapefruit juice, cimetidine) with felodipine may lead to several- fold increases in the plasma levels of felodipine, either due to an increase in bioavailability or due to a decrease in metabolism.


Because of foscarnets tendency to cause renal impairment, the use of FOSCAVIR should be avoided in combination with potentially nephrotoxic drugs such as aminoglycosides, amphotericin B and intravenous pentamidine unless the potential benefits outweigh the risks to the patient.


Therefore, when meclofenamate sodium is given to a patient receiving warfarin, the dosage of warfarin should be reduced to prevent excessive prolongation of the prothrombin time.


Plasma exposure of diazepam (10 mg BID) was increased by 28% following administration of valdecoxib (40 mg BID) for 12 days, while plasma exposure of valdecoxib (40 mg BID) was not substantially increased following administration of diazepam (10 mg BID) for 12 days.


Agents that are CYP3A4 inhibitors that have been found, or are expected, to increase plasma levels of EQUETROTM are the following: Acetazolamide, azole antifungals, cimetidine, clarithromycin(1), dalfopristin, danazol, delavirdine, diltiazem, erythromycin(1), fluoxetine, fluvoxamine, grapefruit juice, isoniazid, itraconazole, ketoconazole, loratadine, nefazodone, niacinamide, nicotinamide, protease inhibitors, propoxyphene, quinine, quinupristin, troleandomycin, valproate(1), verapamil, zileuton.


Drugs that have been associated with peripheral neuropathy include antiretroviral nucleoside analogues, chloramphenicol, cisplatin, dapsone, disulfiram, ethionamide, glutethimide, gold, hydralazine, iodoquinol, isoniazid, metronidazole, nitrofurantoin, phenytoin, ribavirin, and vincristine.


Aspirin should be used cautiously in conjunction with corticosteroids in hypoprothrombinemia.


- a sulfa-based drug such as sulfamethoxazole-trimethoprim (Bactrim, Septra), sulfisoxazole (Gantrisin), or sulfasalazine (Azulfidine);


Nephrotoxicity has been reported following concomitant administration of cephalosporins with aminoglycoside antibiotics or potent diuretics such as furosemide.


Zidovudine should either be temporarily discontinued or decreased by 50% when coadministered with probenecid on the day of VISTIDE infusion.


Although glucocorticoids have been shown to reduce PROLEUKIN-induced side effects including fever, renal insufficiency, hyperbilirubinemia, confusion, and dyspnea, concomitant administration of these agents with PROLEUKIN may reduce the antitumor effectiveness of PROLEUKIN and thus should be avoided. 12 Beta-blockers and other antihypertensives may potentiate the hypotension seen with PROLEUKIN.


Patients taking Acamprosate concomitantly with antidepressants more commonly reported both weight gain and weight loss, compared with patients taking either medication alone.


Binding to Serum Proteins: The following agents may either inhibit levothyroxine sodium binding to serum proteins or alter the concentrations of serum binding proteins: androgens and related anabolic hormones, asparaginase, clofibrate, estrogens and estrogen-containing compounds, 5-fluorouracil, furosemide, glucocorticoids, meclofenamic acid, mefenamic acid, methadone, perphenazine, phenylbutazone, phenytoin, salicylates, tamoxifen.


Certain drugs, including nonsteroidal anti-inflammatory agents (NSAIDs), salicylates, monoamine oxidase inhibitors, and non-selective beta-adrenergic-blocking agents may potentiate the hypoglycemic action of Starlix and other oral antidiabetic drugs.


Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast) should be cautiously coadministered with TIKOSYN as they can potentially increase dofetilide levels.


Estrogen-containing therapies should not be used with ARIMIDEX as they may diminish its pharmacologic action.


Tadalafil dose should not exceed a maximum of 10 mg in a 72- hour period in patients receiving concomitant indinavir therapy.


As a consequence, when INDOCIN and lithium are given concomitantly, the patient should be carefully observed for signs of lithium toxicity.


Concomitant administration of FACTIVE and calcium carbonate, cimetidine, omeprazole, or an estrogen/progesterone oral contraceptive produced minor changes in the pharmacokinetics of gemifloxacin, which were considered to be without clinical significance.


Drugs that induce hepatic enzymes such as phenobarbital, phenytoin and rifampin may increase the clearance of corticosteroids and may require increases in corticosteroid dose to achieve the desired response.


Potassium-sparing diuretics (spironolactone, amiloride,triamterene, and others) or potassium supplements can increase the risk of hyperkalemia.


Although there was a slight reduction in blood sugar concentrations during concomitant administration of flurbiprofen and hypoglycemic agents, there were no signs or symptoms of hypoglycemia.


Agents that are CYP inducers that have been found, or are expected, to decrease plasma levels of EQUETROTM are the following: Cisplatin, doxorubicin HCL, felbamate, rifampin, phenobarbital, Phenytoin(2), primidone, methsuximide, and theophylline Thus, if a patient has been titrated to a stable dosage on EQUETROTM, and then begins a course of treatment with one of these CYP3A4 inducers, it is reasonable to expect that a dose increase for EQUETROTM may be necessary.


Tinnitus and decreased hearing have been reported in patients concomitantly receiving Itraconazole and quinidine.


Ventricular tachycardia induced by ouabain was generally converted to sinus rhythm following administration of Innovar, ketamine, or droperidol but not after administration of fentayl alone or after pentobarbital.


Vasospastic reactions have been reported with therapeutic doses of ergotamine-containing drugs when co-administered with these antibiotics.


apomorphine - prior ingestion of diphenidol may decrease the emetic response to apomorphine in the treatment of poisoning.


The concurrent use of tetracycline and Penthrane (methoxyflurane) has been reported to result in fatal renal toxicity.


However, retinyl acetate stimulated, but did not significantly inhibit, proliferation in the presence of insulin.


Drugs that may alter imatinib plasma concentrations Drugs that may increase imatinib plasma concentrations: Caution is recommended when administering Gleevec with inhibitors of the CYP3A4 family (e.g., ketoconazole, itraconazole, erythromycin, clarithromycin).


Other drugs Drug interactions have been reported with concomitant administration of erythromycin and other medications, including cyclosporine, hexobarbital, carbamazepine, alfentanil, disopyramide, phenytoin, bromocriptine, valproate, astemizole, and lovastatin.


As with other cephalosporins, high concentrations of cefotetan may interfere with measurement of serum and urine creatinine levels by Jaffe  reaction and produce false increases in the levels of creatinine reported.


Curariform muscle relaxants (eg, tubocurarine) and other drugs, including ether, succinylcholine, gallamine, decamethonium and sodium citrate, potentiate the neuromuscular blocking effect and should be used with extreme caution in patients being treated with Coly-Mycin M Parenteral.


Consequently, it is recommended that fluvoxamine not be used in combination with either terbinafine, astemizole, or cisapride.


Agents that are CYP3A4 inhibitors that have been found, or are expected, to increase plasma levels of EQUETROTM are the following: Acetazolamide, azole antifungals, cimetidine, clarithromycin(1), dalfopristin, danazol, delavirdine, diltiazem, erythromycin(1), fluoxetine, fluvoxamine, grapefruit juice, isoniazid, itraconazole, ketoconazole, loratadine, nefazodone, niacinamide, nicotinamide, protease inhibitors, propoxyphene, quinine, quinupristin, troleandomycin, valproate(1), verapamil, zileuton.


Etonogestrel may interact with the following medications: acetaminophen (Tylenol), antibiotics such as ampicillin and tetracycline, anticonvulsants (Dilantin, Phenobarbital, Tegretol, Trileptal, Topamax, Felbatol), antifungals (Gris-PEG, Nizoral, Sporanox), atorvastatin (Lipitor), clofibrate (Atromid-S), cyclosporine (Neoral, Sandimmune), HIV drugs classified as protease inhibitors (Agenerase, Crixivan, Fortovase, Invirase, Kaletra, Norvir, Viracept), morphine (Astramorph, Kadian, MS Contin), phenylbutazone, prednisolone (Prelone), rifadin (rifampin), St. Johns wort, temazepam, theophylline (Theo-Dur), and vitamin C.


Oxytocin or other oxytocics (concurrent use with dinoprost may result in uterine hypertonus, possibly causing uterine rupture or cervical laceration, especially in the absence of adequate cervical dilatation;


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


In one survey, 2.3% of patients taking labetalol HCl in combination with tricyclic antidepressants experienced tremor, as compared to 0.7% reported to occur with labetalol HCl alone.


Co-administration of CYP3A4 inhibitors (eg, ketoconazole, itraconazole, erythromycin, grapefruit juice, cimetidine) with felodipine may lead to several- fold increases in the plasma levels of felodipine, either due to an increase in bioavailability or due to a decrease in metabolism.


Drug Interactions: Flupenthixol may interact with some drugs, like Monoamine oxidase inhibitors (MAOI): MAOI could theoretically affect flupenthixol pharmacodynamics - Arecoline - Eproxindine - Ethanol: Flupenthixol and Ethanol cause additive CNS depression - Tricyclic antidepressants: Flupenthixol increases the effect of Tricyclic antidepressants


SSRIs: Weakness hyperreflexia, and incoordination have been reported rarely when 5-HT1 agonists have been co-administered with SSRIs (e. g.


Concurrent use of erythromycin and ergotamine or dihydroergotamine has been associated in some patients with acute ergot toxicity characterized by severe peripheral vasospasm and dysesthesia.


Therefore, co-administration of tricyclic antidepressants with other drugs that are metabolized by this isoenzyme, including other antidepressants, phenothiazines, carbamazepine, and Type 1C antiarrhythmics (eg, propafenone, flecainide, and encainide), or that inhibit this enzyme (eg, quinidine), should be approached with caution.


Hypersensitivity reactions have been reported in patients receiving combination regimens containing sequential high dose PROLEUKIN and antineoplastic agents, specifically, dacarbazine, cis-platinum, tamoxifen and interferon-alfa.


The administration of local anesthetic solutions containing epinephrine or norepinephrine to patients receiving monoamine oxidase inhibitors or tricyclic antidepressants may produce severe, prolonged hypertension.


Protein Binding In vitro, diclofenac interferes minimally or not at all with the protein binding of salicylic acid (20% decrease in binding), tolbutamide, prednisolone (10% decrease in binding), or warfarin.


Although trough citalopram plasma levels were unaffected, given the enzyme-inducing properties of carbamazepine, the possibility that carbamazepine might increase the clearance of escitalopram should be considered if the two drugs are coadministered.


Anagrelide alone had no effect on platelet aggregation, but did slightly enhance the inhibition of platelet aggregation by aspirin.


Coadministration of entecavir with lamivudine, adefovir dipivoxil,or tenofovir disoproxil fumarate did not result in significant drug interactions.


Concomitant treatment with methylxanthines (aminophylline, theophylline), steroids, or diuretics may potentiate any hypokalemic effect of adrenergic agonists.


Phenobarbital (Primidone): Population pharmacokinetic analyses indicate that tiagabine clearance is 60% greater in patients taking phenobarbital (primidone) with or without other enzyme-inducing AEDs.


Therefore, co-administration of clozapine with other drugs that are metabolized by this isozyme, including antidepressants, phenothiazines, carbamazepine, and Type 1C antiarrhythmics (e.g., propafenone, flecainide and encainide), or that inhibit this enzyme (e.g., quinidine), should be approached with caution.


Drugs that have been reported to diminish oral anticoagulant response, ie, decreased prothrom-bin time response, in man significantly include: adrenocortical steroids;alcohol*;antacids;antihistamines;barbiturates;carbamazepine;chloral hydrate*;chlordiazepoxide;cholestyramine;diet high in vitamin K;diuretics*;ethchlorvynol;glutethimide;griseofulvin;haloperidol;meprobamate;oral contraceptives;paraldehyde;primidone;ranitidine*;rifampin;unreliable prothrombin time determinations;vitamin C;warfarin sodium under-dosage.


Expected to substantially decrease plasma levels of efavirenz;has not been studied in combination with SUSTIVA.


Valproate: Tiagabine causes a slight decrease (about 10%) in steady-state valproate concentrations.


Nephrotoxic agents : Concomitant administration of VISTIDE and agents with nephrotoxic potential [e.g., intravenous aminoglycosides (e.g., tobramycin, gentamicin, and amikacin), amphotericin B, foscarnet, intravenous pentamidine, vancomycin, and non-steroidal anti-inflammatory agents] is contraindicated.


Based on anecdotal reports, there may be an interaction between buprenorphine and benzodiazepines.


Dopamine D2 receptor antagonists (e.g., phenothiazines, butyrophenones, risperidone) and isoniazid may reduce the therapeutic effects of levodopa.


Marked symptomatic orthostatic hypotension has been reported when calcium channel blockers and organic nitrates were used in combination.


Bentiromide may interact with acetaminophen (e.g., Tylenol), chloramphenicol (e.g., Chloromycetin), local anesthetics (e.g., benzocaine and lidocaine), para-aminobenzoic acid (PABA)-containing preparations (e.g., sunscreens and some multivitamins), procainamide (e.g., Pronestyl), sulfonamides (sulfa medicines), thiazide diuretics (use of these medicines during the test period will affect the test results), and pancreatic supplements (use of pancreatic supplements may give false test results).


The concurrent use of two or more drugs with anticholinergic activity--such as an antipsychotic drug (eg, chlorpromazine), an antiparkinsonian drug (eg, trihexyphenidyl), and/or a tricyclic antidepressant (eg, amitriptyline)--commonly results in excessive anticholinergic effects, including dry mouth and associated dental complications, blurred vision, and, in patients exposed to high temperature and humidity, hyperpyrexia.


Preliminary studies indicate that the concomitant use of dobutamine and nitroprusside results in a higher cardiac output and, usually, a lower pulmonary wedge pressure than when either drug is used alone.


Certain drugs including thiazides, corticosteroids, thyroid products, and sympathomimetics may reduce the hypoglycemic action of Starlix and other oral antidiabetic drugs.


Quinolones, including cinoxacin, may enhance the effects of oral anticoagulants, such as warfarin or its derivatives.


However, patients on digoxin may show elevations of digoxin concentrations after initiation of therapy with FLOLAN, which may be clinically significant in patients prone to digoxin toxicity.


H2 Blockers/Proton Pump Inhibitors: Long-term suppression of gastric acid secretion by H2 blockers or proton pump inhibitors (eg, famotidine and omeprazole) is likely to reduce dasatinib exposure.


Nonsteroidal Antiinflammatory Agents: Aspirin is contraindicated in patients who are hypersensitive to nonsteroidal anti-inflammatory agents.


Hypersensitivity Reactions: Patients with a history of severe hypersensitivity reactions to products containing Cremophor  EL (eg, cyclosporin for injection concentrate and teniposide for injection concentrate) should not be treated with TAXOL.


Previous studies have demonstrated a significant reduction in the oral bioavailability of trovafloxacin and ciprofloxacin when administered concomitantly with an intravenous opiate such as morphine.


Nonsteroidal anti-inflammatory drugs have been reported to decrease the tubular secretion of methotrexate and to potentiate its toxicity.


5HT3 Antagonists: Based on reports of profound hypotension and loss of consciousness when apomorphine was administered with ondansetron, the concomitant use of apomorphine with drugs of the 5HT3 antagonist class (including, for example, ondansetron, granisetron, dolasetron, palonosetron, and alosetron) is contraindicated .


In an emergency situation when opioid analgesia must be administered to a patient receiving REVIA, the amount of opioid required may be greater than usual, and the resulting respiratory depression may be deeper and more prolonged.


Therefore the, combination of anakinra with other TNF-blocking agents, including HUMIRA, may also result i n similar toxicities.


Drugs that reportedly may increase oral anticoagulant response, ie, increased prothrombin response, in man include:alcohol*;allopurinol;aminosalicylic acid;amiodarone;anabolic steroids;antibiotics;bromelains;chloral hydrate*;chlorpropamide;chymotrypsin;cimetidine;cinchophen;clofibrate;dextran;dextrothyroxine;diazoxide;dietary deficiencies;diflunisal;disulfiram;drugs affecting blood elements;ethacrynic acid;fenoprofen;glucagon;hepatotoxic drugs;ibuprofen;indomethacin;influenza virus vaccine;inhalation anesthetics;mefenamic acid;methyldopa;methylphenidate;metronidazole;miconazole;monoamine oxidase inhibitors;nalidixic acid;naproxen;oxolinic acid;oxyphenbutazone;pentoxifylline;phenylbutazone;phenyramidol;phenytoin;prolonged hot weather;prolonged narcotics;pyrazolones;quinidine;quinine;ranitidine*;salicylates;sulfinpyrazone;sulfonamides, long acting;sulindac;thyroid drugs;tolbutamide;triclofos sodium;trimethoprim/sulfamethoxazole;unreliable prothrombin time determinations;warfarin sodium overdosage.


Interactions with Other CNS Agents: Concurrent use of Levo-Dromoran with all central nervous system depressants (eg, alcohol, sedatives, hypnotics, other opioids, general anesthetics, barbiturates, tricyclic antidepressants, phenothiazines, tranquilizers, skeletal muscle relaxants and antihistamines) may result in additive central nervous system depressant effects.


The mean percentage increase in the glipizide AUC after fluconazole administration was 56.9% (range: 35 to 81).


INH (Isoniazid) is also reported to affect ketoconazole concentrations adversely.


Chlorotrianisene may interact with antidepressants, aspirin, barbiturates, bromocriptine, calcium supplements, corticosteroids, corticotropin, cyclosporine, dantrolene, nicotine, somatropin, tamoxifen, and warfarin.


This appears to be the only clinically relevant interaction of this kind with Mefloquine, although theoretically, coadministration of other drugs known to alter cardiac conduction (eg, anti-arrhythmic or beta-adrenergic blocking agents, calcium channel blockers, antihistamines or H1-blocking agents, tricyclic antidepressants and phenothiazines) might also contribute to a prolongation of the QTc interval.


These results suggest that both dexamethasone and retinyl acetate, and possibly other glucocorticoids and retinoids, may regulate the proliferation of prostate epithelium by a dose-dependent modification of the activity of insulin and EGF.


Heparin Sodium Injection should not be mixed with doxorubicin, droperidol, ciprofloxacin, or mitoxantrone, since it has been reported that these drugs are incompatible with heparin and a precipitate may form.


Drugs that have been associated with peripheral neuropathy include antiretroviral nucleoside analogues, chloramphenicol, cisplatin, dapsone, disulfiram, ethionamide, glutethimide, gold, hydralazine, iodoquinol, isoniazid, metronidazole, nitrofurantoin, phenytoin, ribavirin, and vincristine.


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


In vitro displacement studies with highly protein-bound drugs such as furosemide, propranolol, captopril, nicardipine, pravastatin, glyburide, warfarin, phenytoin, acetylsalicylic acid, tolbutamide, and metformin showed no influence on the extent of nateglinide protein binding.


Psychoactive Drugs: Hallucinations have been reported when TORADOL was used in patients taking psychoactive drugs (fluoxetine, thiothixene, alprazolam).


Tell your doctor if you are taking any of the following drugs: blood thinners (Coumadin) other antidepressants metoprolol antihistamines carbamazepine (Tegretol) cimetidine (Tagamet) estrogens fluoxetine (Prozac) intraconazole (Sporanox) ketoconazole (Nizoral) levodopa lithium muscle relaxants birth control pills sleeping pills thyroid medications


Studies have shown that lansoprazole does not have clinically significant interactions with other drugs metabolized by the cytochrome P450 system, such as warfarin, antipyrine, indomethacin, ibuprofen, phenytoin, propranolol, prednisone, diazepam, clarithromycin, or terfenadine in healthy subjects.


Blunting of the antihypertensive effect of beta-adrenoceptor blocking agents by non-steroidal antiinflammatory drugs including INDOCIN has been reported.


Thus, smaller doses of adenosine may be effective in the presence of dipyridamole.


therefore, close monitoring of prothrombin time is recommended, and adjustment of the anticoagulant dose may be necessary when Tagamet is administered concomitantly.


Colchicine para-aminosalicylic acid and heavy alcohol intake for longer than 2 weeks may produce malabsorption of vitamin B12.


Similarly, nateglinide had no influence on the serum protein binding of propranolol, glyburide, nicardipine, warfarin, phenytoin, acetylsalicylic acid, and tolbutamide in vitro .


Data from in vitro studies of alprazolam suggest a possible drug interaction with alprazolam for the following: sertraline and paroxetine.


The action of the benzodiazepines may be potentiated by anticonvulsants, antihistamines, alcohol, barbiturates, monoamine oxidase inhibitors, narcotics, phenothiazines, psychotropic medications, or other drugs that produce CNS depression.


Although the interactions observed in these studies do not appear to be of major clinical importance, BREVIBLOC should be titrated with caution in patients being treated concurrently with digoxin, morphine, succinylcholine or warfarin.


In two combined 12-week placebo controlled trials that included BROVANA doses of 15 mcg twice daily, 25 mcg twice daily, and 50 mcg once daily, 54 of 873 BROVANA -treated subjects received concomitant theophylline at study entry.


Indomethacin - Concomitant use of L-glutamine and indomethacin may ameliorate increased intestinal permeability caused by indomethacin.


Agents that are CYP3A4 inhibitors that have been found, or are expected, to increase plasma levels of EQUETROTM are the following: Acetazolamide, azole antifungals, cimetidine, clarithromycin(1), dalfopristin, danazol, delavirdine, diltiazem, erythromycin(1), fluoxetine, fluvoxamine, grapefruit juice, isoniazid, itraconazole, ketoconazole, loratadine, nefazodone, niacinamide, nicotinamide, protease inhibitors, propoxyphene, quinine, quinupristin, troleandomycin, valproate(1), verapamil, zileuton.


Drug Interactions: The central anticholinergic syndrome can occur when anticholinergic agents such as AKINETON are administered concomitantly with drugs that have secondary anticholinergic actions, e.g., certain narcotic analgesics such as meperidine, the phenothiazines and other antipsychotics, tricyclic antidepressants, certain antiarrhythmics such as the quinidine salts, and antihistamines.


Noncardioselective beta-blockers (nadolol,porpranolol,timolol) may exacerbate rebound hypertension when guanfacine is withdrawn.


Other drugs which may enhance the neuromuscular blocking action of nondepolarizing agents such as NIMBEX include certain antibiotics (e. g., aminoglycosides, tetracyclines, bacitracin, polymyxins, lincomycin, clindamycin, colistin, and sodium colistemethate), magnesium salts, lithium, local anesthetics, procainamide, and quinidine.


Concurrent administration of drugs possessing nephrotoxic (e.g., aminoglycosides, indomethacin), myelotoxic (e.g., cytotoxic chemotherapy), cardiotoxic (e.g., doxorubicin) or hepatotoxic (e.g., methotrexate, asparaginase) effects with PROLEUKIN may increase toxicity in these organ systems.


Dosage adjustment of STRATTERA may be necessary when coadministered with CYP2D6 inhibitors, e.g., paroxetine, fluoxetine, and quinidine.


The prior administration of succinylcholine does not enhance the duration, but quickens the onset and may increase the depth, of neuromuscular block induced by TRACRIUM.


Multivalent Cation-Containing Products: Concurrent administration of a quinolone, including ciprofloxacin, with multivalent cation-containing products such as magnesium or aluminum antacids, sucralfate, VIDEX chewable/buffered tablets or pediatric powder, or products containing calcium, iron, or zinc may substantially decrease the absorption of ciprofloxacin, resulting in serum and urine levels considerably lower than desired.


Concomitant use of SPRYCEL and drugs that inhibit CYP3A4 (eg, ketoconazole, itraconazole, erythromycin, clarithromycin, ritonavir, atazanavir, indinavir, nefazodone, nelfinavir, saquinavir, telithromycin) may increase exposure to dasatinib and should be avoided.


Wait 2 weeks after stopping an MAO inhibitor before starting escitalopram.


Considerable caution should be exercised if PEGANONE is administered concurrently with Phenurone (phenacemide) since paranoid symptoms have been reported during therapy with this combination.


There were transient increases in liver ALT and AST when CANCIDAS and cyclosporine were co-administered.


When other potent parental antihypertensive drugs, such as diazoxide, are used in combination with hydralazine, patients should be continuously observed for several hours for any excessive fall in blood pressure.


Theophylline serum levels should be monitored and appropriate dose adjustments considered for patients given both theophylline and PEGASYS.


The clearance of salicylates may be increased with concurrent use of corticosteroids.


Aminosalicylic acid may decrease the amount of digoxin (Lanoxin, Lanoxicaps) that gets absorbed into your body.


Clofibric acid: Combination hormonal contraceptives may increase the clearance of clofibric acid.


Digoxin: Some calcium blockers may increase the concentration of digitalis preparations in the blood.


Caution should be taken when ENABLEX is used concomitantly with medications that are predominantly metabolized by CYP2D6 and which have a narrow therapeutic window, such as flecainide, thioridazine and tricyclic antidepressants (see CLINICAL PHARMACOLOGY).


Lithium: Increased serum lithium levels and symptoms of lithium toxicity have been reported in patients receiving ACE inhibitors during therapy with lithium.


Antidepressants, tricyclic Amphetamines may enhance the activity of tricyclic antidepressants or sympathomimetic agents;


Benzthiazide may interact with alcohol, blood thinners, decongestant drugs (allergy, cold, and sinus medicines), diabetic drugs, lithium, norepinephrine, NSAIDs like Aleve or Ibuprofen, and high blood pressure medications.


Phenobarbital: Coadministration of felbamate with phenobarbital causes an increase in phenobarbital plasma concentrations, In 12 otherwise healthy male volunteers ingesting phenobarbital, the steady-state trough (Cmin) phenobarbital concentration was 14.2 micrograms/mL.


Etonogestrel may interact with the following medications: acetaminophen (Tylenol), antibiotics such as ampicillin and tetracycline, anticonvulsants (Dilantin, Phenobarbital, Tegretol, Trileptal, Topamax, Felbatol), antifungals (Gris-PEG, Nizoral, Sporanox), atorvastatin (Lipitor), clofibrate (Atromid-S), cyclosporine (Neoral, Sandimmune), HIV drugs classified as protease inhibitors (Agenerase, Crixivan, Fortovase, Invirase, Kaletra, Norvir, Viracept), morphine (Astramorph, Kadian, MS Contin), phenylbutazone, prednisolone (Prelone), rifadin (rifampin), St. Johns wort, temazepam, theophylline (Theo-Dur), and vitamin C.


Data from in vitro studies of benzodiazepines other than alprazolam suggest a possible drug interaction for the following: ergotamine, cyclosporine, amiodarone, nicardipine, and nifedipine.


Drugs that reportedly may increase oral anticoagulant response, ie, increased prothrombin response, in man include:alcohol*;allopurinol;aminosalicylic acid;amiodarone;anabolic steroids;antibiotics;bromelains;chloral hydrate*;chlorpropamide;chymotrypsin;cimetidine;cinchophen;clofibrate;dextran;dextrothyroxine;diazoxide;dietary deficiencies;diflunisal;disulfiram;drugs affecting blood elements;ethacrynic acid;fenoprofen;glucagon;hepatotoxic drugs;ibuprofen;indomethacin;influenza virus vaccine;inhalation anesthetics;mefenamic acid;methyldopa;methylphenidate;metronidazole;miconazole;monoamine oxidase inhibitors;nalidixic acid;naproxen;oxolinic acid;oxyphenbutazone;pentoxifylline;phenylbutazone;phenyramidol;phenytoin;prolonged hot weather;prolonged narcotics;pyrazolones;quinidine;quinine;ranitidine*;salicylates;sulfinpyrazone;sulfonamides, long acting;sulindac;thyroid drugs;tolbutamide;triclofos sodium;trimethoprim/sulfamethoxazole;unreliable prothrombin time determinations;warfarin sodium overdosage.


Concomitant administration of FACTIVE and calcium carbonate, cimetidine, omeprazole, or an estrogen/progesterone oral contraceptive produced minor changes in the pharmacokinetics of gemifloxacin, which were considered to be without clinical significance.


Cytochrome P-450 inducers, such as phenytoin, carbamazepine and phenobarbital, induce clonazepam metabolism, causing an approximately 30% decrease in plasma clonazepam levels.


In patients receiving nonselective monoamine oxidase inhibitors (MAOIs) (e.g., selegiline hydrochloride) in combination with serotoninergic agents (e.g., fluoxetine, fluvoxamine, paroxetine, sertraline, venlafaxine), there have been reports of serious, sometimes fatal, reactions.


Aspirin, warfarin, heparin, NSAIDs


Other drugs which may enhance the neuromuscular blocking action of nondepolarizing agents such as NIMBEX include certain antibiotics (e. g., aminoglycosides, tetracyclines, bacitracin, polymyxins, lincomycin, clindamycin, colistin, and sodium colistemethate), magnesium salts, lithium, local anesthetics, procainamide, and quinidine.


These medications have included heparin, warfarin, beta-adrenergic receptor blockers, calcium channel antagonists, angiotensin converting enzyme inhibitors, intravenous and oral nitrates, ticlopidine, and aspirin.


Agents that are CYP3A4 inhibitors that have been found, or are expected, to increase plasma levels of EQUETROTM are the following: Acetazolamide, azole antifungals, cimetidine, clarithromycin(1), dalfopristin, danazol, delavirdine, diltiazem, erythromycin(1), fluoxetine, fluvoxamine, grapefruit juice, isoniazid, itraconazole, ketoconazole, loratadine, nefazodone, niacinamide, nicotinamide, protease inhibitors, propoxyphene, quinine, quinupristin, troleandomycin, valproate(1), verapamil, zileuton.


No clinically significant adverse interactions with commonly used preanesthetic drugs, or drugs used during anesthesia (muscle relaxants, intravenous agents, and local anesthetic agents) were reported in clinical trials.


Due to wide interindividual variability in the dose adjustment required, it is recommended that cyclosporine concentrations be monitored closely after initiation of carvedilol therapy and that the dose of cyclosporine be adjusted as appropriate.


Although specific studies have not been performed, coadministration with drugs that are mainly metabolized by CYP3A4 (eg, calcium channel blockers, dapsone, disopyramide, quinine, amiodarone, quinidine, warfarin, tacrolimus, cyclosporine, ergot derivatives, pimozide, carbamazepine, fentanyl, alfentanyl, alprazolam, and triazolam) may have elevated plasma concentrations when coadministered with saquinavir;


Antacids, Sucralfate, Metal Cations, Multivitamins Quinolones form chelates with alkaline earth and transition metal cations.


This effect may be mediated by the ability of rifampin to induce microsomal enzymes and, thus, the catabolism of warfarin.


Micro-dosed Progesterone Preparations: Micro-dosed progesterone preparations (minipills that do not contain an estrogen) may be an inadequate method of contraception during Accutane therapy.


Butalbital, acetaminophen and caffeine may enhance the effects of: other narcotic analgesics, alcohol, general anesthetics, tranquilizers such as chlordiazepoxide, sedative-hypnotics, or other CNS depressants, causing increased CNS depression.


Drugs and other substances demonstrated to be CYP 3A inhibitors on the basis of clinical studies involving benzodiazepines metabolized similarly to alprazolam or on the basis of in vitro studies with alprazolam or other benzodiazepines (caution is recommended during coadministration with alprazolam): Available data from clinical studies of benzodiazepines other than alprazolam suggest a possible drug interaction with alprazolam for the following: diltiazem, isoniazid, macrolide antibiotics such as erythromycin and clarithromycin, and grapefruit juice.


- The action of sulphonylureas and insulin may be enhanced by Bezalip or Bezalip retard.


Etonogestrel may interact with the following medications: acetaminophen (Tylenol), antibiotics such as ampicillin and tetracycline, anticonvulsants (Dilantin, Phenobarbital, Tegretol, Trileptal, Topamax, Felbatol), antifungals (Gris-PEG, Nizoral, Sporanox), atorvastatin (Lipitor), clofibrate (Atromid-S), cyclosporine (Neoral, Sandimmune), HIV drugs classified as protease inhibitors (Agenerase, Crixivan, Fortovase, Invirase, Kaletra, Norvir, Viracept), morphine (Astramorph, Kadian, MS Contin), phenylbutazone, prednisolone (Prelone), rifadin (rifampin), St. Johns wort, temazepam, theophylline (Theo-Dur), and vitamin C.


Concomitant treatment with methylxanthines (aminophylline, theophylline), steroids, or diuretics may potentiate any hypokalemic effect of adrenergic agonists.


In addition, higher-than expected steady-state serum concentrations of tricyclic antidepressants have been observed when therapy is initiated in patients already taking cimetidine.


Patients receiving both indomethacin and furosemide should be observed closely to determine if the desired diuretic and/or antihypertensive effect of furosemide is achieved.


Patients receiving azathioprine and allopurinol concomitantly should have a dose reduction of azathioprine, to approximately 1/3 to 1/4 the usual dose.


Caution should be used when administering or taking TARCEVA with ketoconazole and other strong CYP3A4 inhibitors such as, but not limited to, atazanavir, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, troleandomycin (TAO), and voriconazole .


Drugs That Should Not Be Coadministered With VIRACEPT Antiarrhythmics: amiodarone, quinidine Antihistamines: astemizole, terfenadine Antimigraine: ergot derivatives Antimycobacterial agents: rifampin Benzodiazepines midazolam, triazolam GI motility agents: cisapride


Other drugs which may enhance the neuromuscular blocking action of nondepolarizing agents such as NIMBEX include certain antibiotics (e. g., aminoglycosides, tetracyclines, bacitracin, polymyxins, lincomycin, clindamycin, colistin, and sodium colistemethate), magnesium salts, lithium, local anesthetics, procainamide, and quinidine.


Medications can interfere with folate utilization, including: anticonvulsant medications (such as phenytoin, and primidone) metformin (sometimes prescribed to control blood sugar in type 2 diabetes) sulfasalazine (used to control inflammation associated with Crohns disease and ulcerative colitis) triamterene (a diuretic) Methotrexate There has been concern about the interaction between vitamin B12 and folic acid.


Codeine in combination with other narcotic analgesics, general anesthetics, phenothiazines, tranquilizers, sedative-hypnotics, or other CNS depressants (including alcohol) has additive depressant effects.


Interactions for vitamin D analogues (Vitamin D2, Vitamin D3, Calcitriol, and Calcidiol): Cholestyramine: Cholestyramine has been reported to reduce intestinal absorption of fat soluble vitamins;


Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast) should be cautiously coadministered with TIKOSYN as they can potentially increase dofetilide levels.


Drugs which induce CYP3A4 activity (eg, phenobarbital, rifampin, rifabutin) would be expected to increase the clearance of efavirenz resulting in lowered plasma concentrations.


Thus, careful monitoring of clinical status is warranted when rifampin is administered or discontinued in haloperidol-treated patients.


Although additional drug interaction studies have not been conducted, the most common medications used concomitantly with anagrelide in clinical trials were aspirin, acetaminophen, furosemide, iron, ranitidine, hydroxyurea, and allopurinol.


The benzodiazepines, including alprazolam, produce additive CNS depressant effects when co-administered with other psychotropic medications, anticonvulsants, antihistaminics, ethanol, and other drugs which themselves produce CNS depression.


These drugs include the thiazides and other diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel blocking drugs, and isoniazid.


Acellular, live and live-attenuated vaccines should not be administered during RAPTIVA treatment.


Probenecid: Concomitant administration of TORADOL ORAL and probenecid resulted in decreased clearance of ketorolac and significant increases in ketorolac plasma levels (total AUC increased approximately threefold from 5.4 to 17.8 m g/h/mL) and terminal half-life increased approximately twofold from 6.6 to 15.1 hours.


Non-steroidal Anti-inflammatory Drugs: In some patients, the administration of a non-steroidal anti-inflammatory agent can reduce the diuretic, natriuretic, and antihypertensive effects of loop, potassium-sparing and thiazide diuretics.


Monoamine oxidase (MAO) inhibitors such as isocarboxazid (e.g., Marplan), phenelzine (e.g., Nardil), procarbazine (e.g., Matulane), selegiline (e.g., Eldepryl), and tranylcypromine (e.g., Parnate): Using these medicines with L-tryptophan may increase the chance of side effects.


Digitalis: Vitamin D dosage must be determined with care in patients undergoing treatment with digitalis, as hypercalcemia in such patients may precipitate cardiac arrhythmias.


Clinical trials have indicated that Pulmozyme can be effectively and safely used in conjunction with standard cystic fibrosis therapies including oral, inhaled and/or parenteral antibiotics, bronchodilators, enzyme supplements, vitamins, oral or inhaled corticosteroids, and analgesics.


Concurrent administration of etanercept (another TNF -blocking agent) and anakinra (an interleukin-1 antagonist) has been associated with an increased risk of serious infections, and increased risk of neutropenia and no additional benefit compared to these medicinal products alone.


The serum concentration of phenytoin increased dramatically from 16.6 to 49.1 microg/mL when fluvoxamine was coadministered, although the daily dosage of phenytoin and other drugs had not changed.


Therefore, co-administration of bupropion with drugs that are metabolized by CYP2D6 isoenzyme including certain antidepressants (e.g., nortriptyline, imipramine, desipramine, paroxetine, fluoxetine, sertraline), antipsychotics (e.g., haloperidol, risperidone, thioridazine), beta-blockers (e.g., metoprolol), and Type 1C antiarrhythmics (e.g., propafenone, flecainide), should be approached with caution and should be initiated at the lower end of the dose range of the concomitant medication.


Drugs that have been reported to diminish oral anticoagulant response, ie, decreased prothrom-bin time response, in man significantly include: adrenocortical steroids;alcohol*;antacids;antihistamines;barbiturates;carbamazepine;chloral hydrate*;chlordiazepoxide;cholestyramine;diet high in vitamin K;diuretics*;ethchlorvynol;glutethimide;griseofulvin;haloperidol;meprobamate;oral contraceptives;paraldehyde;primidone;ranitidine*;rifampin;unreliable prothrombin time determinations;vitamin C;warfarin sodium under-dosage.


These results suggest that both dexamethasone and retinyl acetate, and possibly other glucocorticoids and retinoids, may regulate the proliferation of prostate epithelium by a dose-dependent modification of the activity of insulin and EGF.


Chlorpromazine: Chlorpromazine blocks dopamine and norepinephrine reuptake, thus inhibiting the central stimulant effects of amphetamines, and can be used to treat amphetamine poisoning.


ERYTHROMYCIN: In hypercholesterolemic patients, steady-state cerivastatin AUC and Cmax increased approximately 50% and 24% respectively after 10 days with co-administration of erythromycin, a known inhibitor of cytochrome P450 3A4.


Concurrent administration of drugs possessing nephrotoxic (e.g., aminoglycosides, indomethacin), myelotoxic (e.g., cytotoxic chemotherapy), cardiotoxic (e.g., doxorubicin) or hepatotoxic (e.g., methotrexate, asparaginase) effects with PROLEUKIN may increase toxicity in these organ systems.


In vitro studies have shown that the metabolism of docetaxel may be modified by the concomitant administration of compounds that induce, inhibit, or are metabolized by cytochrome P450 3A4, such as cyclosporine, terfenadine, ketoconazole, erythromycin, and troleandomycin.


- Perhexiline hydrogen maleate or MAO-inhibitors (with hepatotoxic potential) must not be administered together with Bezalip or Bezalip retard.


Although BETAGAN used alone has little or no effect on pupil size, mydriasis resulting from concomitant therapy with BETAGAN and epinephrine may occur.


Concurrent use of tetracyclines with oral contraceptives may render oral contraceptives less effective.


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


This appears to be the only clinically relevant interaction of this kind with Mefloquine, although theoretically, coadministration of other drugs known to alter cardiac conduction (eg, anti-arrhythmic or beta-adrenergic blocking agents, calcium channel blockers, antihistamines or H1-blocking agents, tricyclic antidepressants and phenothiazines) might also contribute to a prolongation of the QTc interval.


Coadministration of almotriptan and the potent CYP3A4 inhibitor ketoconazole (400 mg q.d. for 3 days) resulted in an approximately 60% increase in the area under the plasma concentration-time curve and maximal plasma concentrations of almotriptan.


Antibiotics: In vitro and/or in vivo data show that clarithromycin, erythromycin, and troleandomycin markedly inhibit the metabolism of cisapride, which can result in an increase in plasma cisapride levels and prolongation of the QT interval on the ECG.


Studies have shown that lansoprazole does not have clinically significant interactions with other drugs metabolized by the cytochrome P450 system, such as warfarin, antipyrine, indomethacin, ibuprofen, phenytoin, propranolol, prednisone, diazepam, clarithromycin, or terfenadine in healthy subjects.


Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast) should be cautiously coadministered with TIKOSYN as they can potentially increase dofetilide levels.


Sumatriptan and D.H.E. 45  (dihydroergotamine mesylate) Injection, USP should not be taken within 24 hours of each other..


Concomitant use of SPRYCEL and drugs that inhibit CYP3A4 (eg, ketoconazole, itraconazole, erythromycin, clarithromycin, ritonavir, atazanavir, indinavir, nefazodone, nelfinavir, saquinavir, telithromycin) may increase exposure to dasatinib and should be avoided.


H2 Blockers/Proton Pump Inhibitors: Long-term suppression of gastric acid secretion by H2 blockers or proton pump inhibitors (eg, famotidine and omeprazole) is likely to reduce dasatinib exposure.


ketoconazole), macrolide antibiotics (e.g. erythromycin), and HIV protease inhibitors (e.g. ritonavir, indinavir and saquinavir) should have their dose of SUBUTEX or SUBOXONE adjusted.


Due to wide interindividual variability in the dose adjustment required, it is recommended that cyclosporine concentrations be monitored closely after initiation of carvedilol therapy and that the dose of cyclosporine be adjusted as appropriate.


Both the magnitude and duration of central nervous system and cardiovascular effects may be enhanced when ALFENTA is administered in combination with other CNS depressants such as barbiturates, tranquilizers, opioids, or inhalation general anesthetics.


Monitoring for amiodarone toxicity and serial measurement of amiodarone serum concentration during concomitant protease inhibitor therapy should be considered.


Injection: Lorazepam injection, like other injectable benzodiazepines, produces depression of the central nervous system when administered with ethyl alcohol, phenothiazines, barbiturates, MAO inhibitors, and other antidepressants.When scopolamine is used concomitantly with injectable lorazepam, an increased incidence of sedation, hallucinations, and irrational behavior has been observed.


In vitro displacement studies with highly protein-bound drugs such as furosemide, propranolol, captopril, nicardipine, pravastatin, glyburide, warfarin, phenytoin, acetylsalicylic acid, tolbutamide, and metformin showed no influence on the extent of nateglinide protein binding.


The action of the benzodiazepines may be potentiated by anticonvulsants, antihistamines, alcohol, barbiturates, monoamine oxidase inhibitors, narcotics, phenothiazines, psychotropic medications, or other drugs that produce CNS depression.


Binding to Serum Proteins: The following agents may either inhibit levothyroxine sodium binding to serum proteins or alter the concentrations of serum binding proteins: androgens and related anabolic hormones, asparaginase, clofibrate, estrogens and estrogen-containing compounds, 5-fluorouracil, furosemide, glucocorticoids, meclofenamic acid, mefenamic acid, methadone, perphenazine, phenylbutazone, phenytoin, salicylates, tamoxifen.


Haloperidol: Haloperidol blocks dopamine receptors, thus inhibiting the central stimulant effects of amphetamines.


In patients receiving another serotonin reuptake inhibitor drug in combination with monoamine oxidase inhibitors (MAOI), there have been reports of serious, sometimes fatal, reactions including hyperthermia, rigidity, myoclonus, autonomic instability with possible rapid fluctuations of vital signs, and mental status changes that include extreme agitation progressing to delirium and coma.


Although no specific drug interactions with topical glaucoma drugs or systemic medications were identified in clinical studies of IOPIDINE 0.5% Ophthalmic Solution, the possibility of an additive or potentiating effect with CNS depressants (alcohol, barbiturates, opiates, sedatives, anesthetics) should be considered.


A two-way interaction between the hydantoin antiepileptic, phenytoin, and the coumarin anticoagulants has been suggested.


Curariform muscle relaxants (eg, tubocurarine) and other drugs, including ether, succinylcholine, gallamine, decamethonium and sodium citrate, potentiate the neuromuscular blocking effect and should be used with extreme caution in patients being treated with Coly-Mycin M Parenteral.


Geocillin (carbenicillin indanyl sodium) blood levels may be increased and prolonged by concurrent administration of probenecid.


There is one report suggesting that the concomitant use of trazodone hydrochloride (Desyrel) and buspirone HCl may have caused 3- to 6-fold elevations on SGPT (ALT) in a few patients.


In vitro studies have shown CASODEX can displace coumarin anticoagulants, such as warfarin, from their protein-binding sites.


When used in therapeutic doses, azithromycin had a modest effect on the pharmacokinetics of atorvastatin, carbamazepine, cetirizine, didanosine, efavirenz, fluconazole, indinavir, midazolam, rifabutin, sildenafil, theophylline (intravenous and oral), triazolam, trimethoprim/sulfamethoxazole or zidovudine.


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


It is recommended that in patients taking anticoagulants, prothrombin time be determined before starting lovastatin and frequently enough during early therapy to insure that no significant alteration of prothrombin time occurs.


Following the administration of INAPSINE, the dose of other CNS depressant drugs should be reduced.


Drug Interactions: The central anticholinergic syndrome can occur when anticholinergic agents such as AKINETON are administered concomitantly with drugs that have secondary anticholinergic actions, e.g., certain narcotic analgesics such as meperidine, the phenothiazines and other antipsychotics, tricyclic antidepressants, certain antiarrhythmics such as the quinidine salts, and antihistamines.


Antacid: When atorvastatin and Maalox TC suspension were coadministered, plasma concentrations of atorvastatin decreased approximately 35%.


Specific Effects of Felbatol  on Other Antiepileptic Drugs Phenytoin: Felbatol  causes an increase in steady-state phenytoin plasma concentrations.


Theophylline-related adverse effects have occurred in patients when theophylline and enoxacin were coadministered.


Thyroid Physiology: The following agents may alter thyroid hormone or TSH levels, generally by effects on thyroid hormone synthesis, secretion, distribution, metabolism, hormone action, or elimination, or altered TSH secretion: aminoglutethimide, p-aminosalicylic acid, amiodarone, androgens and related anabolic hormones, complex anions (thiocyanate, perchlorate, pertechnetate), antithyroid drugs, b-adrenergic blocking agents, carbamazepine, chloral hydrate, diazepam, dopamine and dopamine agonists, ethionamide, glucocorticoids, heparin, hepatic enzyme inducers, insulin, iodinated cholestographic agents, iodine-containing compounds, levodopa, lovastatin, lithium, 6-mercaptopurine, metoclopramide, mitotane, nitroprusside, phenobarbital, phenytoin, resorcinol, rifampin, somatostatin analogs, sulfonamides, sulfonylureas, thiazide diuretics.


- Phenothiazines (acetophenazine [e.g., Tindal], chlorpromazine [e.g., Thorazine], fluphenazine [e.g., Prolixin], mesoridazine [e.g., Serentil], perphenazine [e.g., Trilafon], prochlorperazine [e.g., Compazine], promazine [e.g., Sparine], promethazine [e.g., Phenergan], thioridazine [e.g., Mellaril], trifluoperazine [e.g., Stelazine], triflupromazine [e.g., Vesprin], trimeprazine [e.g., Temaril]) or


Therefore, co-administration of Duloxetine with other drugs that are extensively metabolized by this isozyme and which have a narrow therapeutic index, including certain antidepressants (tricyclic antidepressants [TCAs], such as nortriptyline, amitriptyline, and imipramine), phenothiazines and Type 1C antiarrhythmics (e.g., propafenone, flecainide), should be approached with caution.


astemizole, bepridil, sparfloxacin, and terodiline.


Effects of Erythromycin on Felbatol  The coadministration of erythromycin (1000 mg/day) for 10 days did not alter the pharmacokinetic parameters of Cmax, Cmin, AUC, CI/kg or tmax at felbamate daily doses of 3000 or 3600 mg/day in 10 otherwise healthy subjects with epilepsy.


- Drugs whose efficacy is impaired by phenytoin include: anticoagulants, corticosteroids, coumarin, digitoxin, doxycycline, estrogens, furosemide, oral contraceptives, rifampin, quinidine, theophylline, vitamin D.


While all the selective serotonin reuptake inhibitors (SSRIs), e. g., fluoxetine, sertraline, and paroxetine, inhibit P450 2D6, they may vary in the extent of inhibition.


Cardiac effects of dopamine are antagonized by beta-adrenergic blocking agents, such as propranolol and metoprolol.


As with other antipsychotic agents, it should be noted that HALDOL may be capable of potentiating CNS depressants such as anesthetics, opiates, and alcohol.


Both efavirenz and nevirapine have been compared to triple therapy with the PI indinavir over 48 weeks as initial therapy, with similar responses being observed with nevirapine regimens and superiority observed with efavirenz.


H2 Blockers/Proton Pump Inhibitors: Long-term suppression of gastric acid secretion by H2 blockers or proton pump inhibitors (eg, famotidine and omeprazole) is likely to reduce dasatinib exposure.


Lithium: NSAIDs have produced an elevation of plasma lithium levels and a reduction in renal lithium clearance.


Although it has not been established that there is an interaction between Clozapine and benzodiazepines or other psychotropics, caution is advised when clozapine is initiated in patients taking a benzodiazepine or any other psychotropic drug.


Epinephrine also should be used cautiously with other drugs (e.g., digitalis, glycosides) that sensitize the myocardium to the actions of sympathomimetic drugs.


In diabetic patients, the metabolic effects of androgens may decrease blood glucose and therefore, insulin requirements.


Etonogestrel may interact with the following medications: acetaminophen (Tylenol), antibiotics such as ampicillin and tetracycline, anticonvulsants (Dilantin, Phenobarbital, Tegretol, Trileptal, Topamax, Felbatol), antifungals (Gris-PEG, Nizoral, Sporanox), atorvastatin (Lipitor), clofibrate (Atromid-S), cyclosporine (Neoral, Sandimmune), HIV drugs classified as protease inhibitors (Agenerase, Crixivan, Fortovase, Invirase, Kaletra, Norvir, Viracept), morphine (Astramorph, Kadian, MS Contin), phenylbutazone, prednisolone (Prelone), rifadin (rifampin), St. Johns wort, temazepam, theophylline (Theo-Dur), and vitamin C.


Isoflurane or enflurane administered with nitrous oxide/oxygen to achieve 1.25 MAC [Minimum Alveolar Concentration] may prolong the clinically effective duration of action of initial and maintenance doses of NIMBEX and decrease the required infusion rate of NIMBEX.


Caution should be exercised during the administration of adrenaline to patients anaesthetised with FLUOTHANE as arrhythmias may be precipitated.


Spontaneous reports of serotonin syndrome associated with co-administration of ZYVOX and serotonergic agents, including antidepressants such as selective serotonin reuptake inhibitors (SSRIs), have been reported.


Clozapine may potentiate the hypotensive effects of antihypertensive drugs and the anticholinergic effects of atropine-type drugs.


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


The antihypertensive effects of methyldopa, mecamylamine, reserpine, and veratrum alkaloids may be reduced by sympathomimetics.


In addition to bleeding associated with heparin and vitamin K antagonists, drugs that alter platelet function (such as acetylsalicylic acid, dipyridamole and Abciximab) may increase the risk of bleeding if administered prior to, during, or after Activase therapy.


The patient was also chronically receiving phenytoin, phenobarbital, digoxin, and levothyroxine sodium.


Drugs that have been associated with peripheral neuropathy include antiretroviral nucleoside analogues, chloramphenicol, cisplatin, dapsone, disulfiram, ethionamide, glutethimide, gold, hydralazine, iodoquinol, isoniazid, metronidazole, nitrofurantoin, phenytoin, ribavirin, and vincristine.


Co-administration of lovastatin, atenolol, warfarin, furosemide, digoxin, celecoxib, hydrochlorothiazide, ramipril, valsartan, metformin and amlodipine did not result in clinically significant increases in aliskiren exposure.


Infusion requirements of NIMBEX in patients administered succinylcholine prior to infusions of NIMBEX were comparable to or slightly greater than when succinylcholine was not administered.


Tablets: The benzodiazepines, including lorazepam, produce CNS-depressant effects when administered with such medications as barbiturates or alcohol.


Tagamet, apparently through an effect on certain microsomal enzyme systems, has been reported to reduce the hepatic metabolism of warfarin-type anticoagulants, phenytoin, propranolol, nifedipine, chlordiazepoxide, diazepam, certain tricyclic antidepressants, lidocaine, theophylline and metronidazole, thereby delaying elimination and increasing blood levels of these drugs.


Cytochalasin D inhibited the carbachol-stimulated intracellular Ca(2+) concentration ([Ca(2+)](i)) increase due to release from the Ca(2+) store.


Methotrexate: NSAIDs have been reported to competitively inhibit methotrexate accumulation in rabbit kidney slices.


In order to examine some molecular mechanisms of PCP-induced behavioral changes, Northern blot analysis of total RNA from prefrontal cortical tissues of mice treated with PCP, DCG-IV, and L-CCG-1 was carried out.


Other drugs which may enhance the neuromuscular blocking action of nondepolarizing agents such as NIMBEX include certain antibiotics (e. g., aminoglycosides, tetracyclines, bacitracin, polymyxins, lincomycin, clindamycin, colistin, and sodium colistemethate), magnesium salts, lithium, local anesthetics, procainamide, and quinidine.


While all the selective serotonin reuptake inhibitors (SSRIs), e.g., citalopram, escitalopram, fluoxetine, sertraline, and paroxetine, inhibit P450 2D6, they may vary in the extent of inhibition.


In some patients, the administration of INDOCIN can reduce the diuretic, natriuretic, and antihypertensive effects of loop, potassium-sparing, and thiazide diuretics.


Close observation of the patient is recommended when a beta-blocker is administered to patients receiving catecholamine-depleting drugs such as reserpine, because of possible additive effects and the production of hypotension and/or marked bradycardia, which may produce vertigo, syncope or postural hypotension.


Netilmicin should not be administered concomitantly with potent loop diuretics such as furosemide and ethacrynic acid as the potential for ototoxicity is enhanced by the combination.


Substances that are potent inhibitors of CYP3A4 activity (eg, ketoconazole and itraconazole) decrease gefitinib metabolism and increase gefitinib plasma concentrations.


poor metabolizers of debrisoquin: Interactions of carvedilol with strong inhibitors of CYP2D6 (such as quinidine, fluoxetine, paroxetine, and propafenone) have not been studied, but these drugs would be expected to increase blood levels of the R(+) enantiomer of carvedilol .


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


MAO Inhibitors: DURAGESIC  is not recommended for use in patients who have received MAOI within 14 days because severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics


Anticoagulants including coumarin derivatives, indandione derivatives, and platelet aggregation inhibitors such as nonsteroidal anti-inflammatory drugs (NSAIDs), and aspirin may increase the risk of bleeding when administered concomitantly with ardeparin.


The action of the benzodiazepines may be potentiated by anticonvulsants, antihistamines, alcohol, barbiturates, monoamine oxidase inhibitors, narcotics, phenothiazines, psychotropic medications, or other drugs that produce CNS depression.


Butyrophenones (such as haloperidol) and phenothiazines can suppress the dopaminergic renal and mesenteric vasodilation induced with low dose dopamine infusion.


Chlorotrianisene may interact with antidepressants, aspirin, barbiturates, bromocriptine, calcium supplements, corticosteroids, corticotropin, cyclosporine, dantrolene, nicotine, somatropin, tamoxifen, and warfarin.


Vaccines: Patients on corticosteroid therapy may exhibit a diminished response to toxoids and live or inactivated vaccines due to inhibition of antibody response.


Methadone: Coadministration of amprenavir and methadone can decrease plasma levels of methadone.


The following are examples of substances that may reduce the blood-glucose-lowering effect: corticosteroids, niacin, danazol, diuretics, sympathomimetic agents (e.g., epinephrine, salbutamol, terbutaline), isoniazid, phenothiazine derivatives, somatropin, thyroid hormones, estrogens, progestogens (e.g., in oral contraceptives).


Interactions with Other CNS Agents: Concurrent use of Levo-Dromoran with all central nervous system depressants (eg, alcohol, sedatives, hypnotics, other opioids, general anesthetics, barbiturates, tricyclic antidepressants, phenothiazines, tranquilizers, skeletal muscle relaxants and antihistamines) may result in additive central nervous system depressant effects.


Concomitant Administration with Racemic Citalopram Citalopram - Since escitalopram is the active isomer of racemic citalopram (Celexa), the two agents should not be coadministered.


In clinical trials in patients undergoing PTCA/PCI, co-administration of Angiomax with heparin, warfarin, thrombolytics or glycoprotein IIb/IIIa inhibitors was associated with increased risks of major bleeding events compared to patients not receiving these concomitant medications.


If rifampicin therapy is required, isradipine concentrations and therapeutic effects are likely to be markedly reduced or abolished as a consequence of increased metabolism and higher clearance of isradipine.


Erythromycin: In healthy individuals, plasma concentrations of atorvastatin increased approximately 40% with coadministration of atorvastatin and erythromycin, a known inhibitor of cytochrome P450 3A4.


In addition, results from regression analyses of patient pharmacokinetic data suggest that co-administration of other inducers of drug clearance (efavirenz, nevirapine, phenytoin, dexamethasone, or carbamazepine) with CANCIDAS may result in clinically meaningful reductions in caspofungin concentrations.


Isoflurane potentiates the muscle relaxant effect of all muscle relaxants, most notably nondepolarizing muscle relaxants, and MAC (minimum alveolar concentration) is reduced by concomitant administration of N 2O.


Dexbrompheniramine can interact with alcohol or other CNS depressants (may potentiate the CNS depressant effects of either these medications or antihistamines), anticholinergics or other medications with anticholinergic activity (anticholinergic effects may be potentiated when these medications are used concurrently with antihistamines), and monoamine oxidase (MAO) inhibitors (concurrent use with antihistamines may prolong and intensify the anticholinergic and CNS depressant effects of antihistamines).


Sildenafil is contraindicated in patients using long-acting nitrates or who may need to use short-acting nitrates, because the combination may cause a sharp fall of the blood pressure.


Netilmicin should not be administered concomitantly with potent loop diuretics such as furosemide and ethacrynic acid as the potential for ototoxicity is enhanced by the combination.


Two different types of therapy with magnesium are used: physiological oral magnesium supplementation which is totally atoxic since it palliates magnesium deficiencies by simply normalizing the magnesium intake and pharmacological magnesium therapy which may induce toxicity since it creates iatrogenic magnesium overload.


In a placebo-controlled trial in normal volunteers, the administration of a single 1 mg dose of doxazosin on day 1 of a four-day regimen of oral cimetidine (400 mg twice daily) resulted in a 10% increase in mean AUC of doxazosin (p=0.006), and a slight but not statistically significant increase in mean Cmax and mean half-life of doxazosin.


Drugs Whose Absorption Can Be Affected by the Level of Acidity in the Stomach: Drugs such as ketoconazole and itraconazole should be administered at least 2 hours prior to dosing with VIDEX.


Concurrent use of erythromycin and ergotamine or dihydroergotamine has been associated in some patients with acute ergot toxicity characterized by severe peripheral vasospasm and dysesthesia.


Other drugs which may enhance the neuromuscular blocking action of nondepolarizing agents such as NUROMAX include certain antibiotics (e. g., aminoglycosides, tetracyclines, bacitracin, polymyxins, lincomycin, clindamycin, colistin, and sodium colistimethate), magnesium salts, lithium, local anesthetics, procainamide, and quinidine.


Drugs that reportedly may increase oral anticoagulant response, ie, increased prothrombin response, in man include:alcohol*;allopurinol;aminosalicylic acid;amiodarone;anabolic steroids;antibiotics;bromelains;chloral hydrate*;chlorpropamide;chymotrypsin;cimetidine;cinchophen;clofibrate;dextran;dextrothyroxine;diazoxide;dietary deficiencies;diflunisal;disulfiram;drugs affecting blood elements;ethacrynic acid;fenoprofen;glucagon;hepatotoxic drugs;ibuprofen;indomethacin;influenza virus vaccine;inhalation anesthetics;mefenamic acid;methyldopa;methylphenidate;metronidazole;miconazole;monoamine oxidase inhibitors;nalidixic acid;naproxen;oxolinic acid;oxyphenbutazone;pentoxifylline;phenylbutazone;phenyramidol;phenytoin;prolonged hot weather;prolonged narcotics;pyrazolones;quinidine;quinine;ranitidine*;salicylates;sulfinpyrazone;sulfonamides, long acting;sulindac;thyroid drugs;tolbutamide;triclofos sodium;trimethoprim/sulfamethoxazole;unreliable prothrombin time determinations;warfarin sodium overdosage.


Concomitant administration of Sonata (10 mg) and cimetidine (800 mg) produced an 85% increase in the mean Cmax and AUC of zaleplon.


Before taking glimepiride, tell your doctor if you are taking any of the following medicines: - aspirin or another salicylate such as magnesium/choline salicylate (Trilisate), salsalate (Disalcid, others), choline salicylate (Arthropan), magnesium salicylate (Magan), or bismuth subsalicylate (Pepto-Bismol);


For this reason, the dose of the anticoagulant should be reduced by 30 - 50% at the start of treatment with Bezalip or Bezalip retard and then titrated according to the blood clotting parameters


Cyclosporine: Administration of nonsteroial anti-inflammatory drugs concomitantly with cyclosporine has been associated with an increase in cyclosporine-induced toxicity, possibly due to decreased synthesis of renal prostacyclin.


Oral doses of Antizol (10-20 mg/kg), via alcohol dehydrogenase inhibition, significantly reduced the rate of elimination of ethanol (by approximately 40%) given to healthy volunteers in moderate doses.


These drugs include the thiazides and other diuretics, corticosteroids, phenothiazines, thyroid products, estrogens, oral contraceptives, phenytoin, nicotinic acid, sympathomimetics, calcium channel-blocking drugs, and isoniazid.


The administration of other potassium-sparing antihypertensives with NSAIDs has been shown to reduce the antihypertensive effect in some patients and result in severe hyperkalemia in patients with impaired renal function.


Digitalis toxicity may be aggravated by the initial release of norepinephrine caused by Bretylium Tosylate Injection.


The risk of a potential interaction between NovoSeven and coagulation factor concentrates has not been adequately evaluated in preclinical or clinical studies.


Drugs that have been reported to diminish oral anticoagulant response, ie, decreased prothrom-bin time response, in man significantly include: adrenocortical steroids;alcohol*;antacids;antihistamines;barbiturates;carbamazepine;chloral hydrate*;chlordiazepoxide;cholestyramine;diet high in vitamin K;diuretics*;ethchlorvynol;glutethimide;griseofulvin;haloperidol;meprobamate;oral contraceptives;paraldehyde;primidone;ranitidine*;rifampin;unreliable prothrombin time determinations;vitamin C;warfarin sodium under-dosage.


Selegiline: Combination hormonal contraceptives may increase the serum concentration of selegiline.


METHOD: This study was a multicenter randomized double-blind study of 101 patients who were randomly assigned 1:1:1 to receive everolimus tablets at doses of 0.5 mg, 1 mg, or 2 mg twice daily with cyclosporine and prednisone.


Therefore, when INDOCIN and digoxin are used concomitantly, serum digoxin levels should be closely monitored.


Diuretics: Patients on diuretics, especially those with intravascular volume depletion, may occasionally experience an excessive reduction of blood pressure after initiation of therapy with fosinopril sodium.


Bacteriostatic Antibiotics: Chloramphenicol, erythromycins, sulfonamides, or tetracyclines may interfere with the bactericidal effect of penicillins.


Etofibrate elicited 62% enhancement of post-heparin lipolytic activity and 100% increase of 3H-triglyceride fractional clearance rate compared with placebo treatment.


It is recommended to avoid concurrent administration of ethambutol with aluminum hydroxide containing antacids for at least 4 hours following ethambutol administration.


The purpose of this study was to evaluate the effect of sodium carboxymethylcellulose (NaCMC) and carboxymethylcellulose-cysteine (CMC-Cys) conjugates on the intestinal permeation of sodium fluorescein (NaFlu) and model peptide drugs, bacitracin and insulin.


Administration of eplerenone with other CYP3A4 inhibitors (e.g., erythromycin 500 mg BID, verapamil 240 mg QD, saquinavir 1200 mg TID, fluconazole 200 mg QD) resulted in increases in Cmax of eplerenone ranging from 1.4- to 1.6- fold and AUC from 2.0- to 2.9- fold.


Aortic rings with intact endothelium from the high-dose (4 mg/kg/day) estradiol group were supersensitive to noradrenaline compared to the vehicle or low-dose (10 microg/kg/day) estradiol groups (pD2 values = 7.86+/-0.09, 7.30+/-0.11 and 7.35+/-0.04, respectively).


The potential effects of increased plasma concentrations of midazolam or other benzodiazepines metabolized via CYP3A4 (alprazolam, triazolam) should be considered when coadministering these agents with Aprepitant.


Antineoplastic agents (e. g., nitrogen mustard, etc.) should be given concomitantly only with great caution.


Therefore, co-administration of Duloxetine with other drugs that are extensively metabolized by this isozyme and which have a narrow therapeutic index, including certain antidepressants (tricyclic antidepressants [TCAs], such as nortriptyline, amitriptyline, and imipramine), phenothiazines and Type 1C antiarrhythmics (e.g., propafenone, flecainide), should be approached with caution.


Drugs such as troleandomycin and ketoconazole may inhibit the metabolism of corticosteroids and thus decrease their clearance.


Upon administration of 10 mg of Vardenafil with 800 mg TID indinavir, the Cmax and AUC of indinavir were reduced by 40% and 30%, respectively.


HMG-CoA reductase inhibitors: The combined use of TRICOR and HMG-CoA reductase inhibitors should be avoided unless the benefit of further alterations in lipid levels is likely to outweigh the increased risk of this drug combination.


Corticosteroids: A relationship of functional antagonism exists between vitamin D analogues, which promote calcium absorption, and corticosteroids, which inhibit calcium absorption.


acetaminophen/theophylline, lidocaine/quinidine, phenobarbital/acetaminophen, phenobarbital/valproic acid, quinidine/lidocaine, theophylline/acetaminophen, and valproic acid/phenobarbital.


Chlorpropamide: Chlorpropamides plasma half-life may be prolonged by allopurinol, since allopurinol and chlorpropamide may compete for excretion in the renal tubule.


There was no evidence of drug interactions in clinical studies in which dobutamine was administered concurrently with other drugs, including digitalis preparations, furosemide, spironolactone, lidocaine, glyceryl trinitrate, isosorbide dinitrate, morphine, atropine, heparin, protamine, potassium chloride, folic acid, and acetaminophen.


Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast) should be cautiously coadministered with TIKOSYN as they can potentially increase dofetilide levels.


plasma levels of several closely related tricyclic antidepressants have been reported to be increased by the concomitant administration of methylphenidate or hepatic enzyme inhibitors (e.g., cimetidine, fluoxetine) and decreased by the concomitant administration of hepatic enzyme inducers (e.g., barbiturates, phenytoin), and such an effect may be anticipated with CMI as well.


Elevated cyclosporine serum levels have been reported with the concomitant use of quinolones and cyclosporine.


Lymphocytopenia has been reported in patients receiving CAMPTOSAR, and it is possible that the administration of dexamethasone as antiemetic prophylaxis may have enhanced the likelihood of this effect.


5HT3 Antagonists: Based on reports of profound hypotension and loss of consciousness when apomorphine was administered with ondansetron, the concomitant use of apomorphine with drugs of the 5HT3 antagonist class (including, for example, ondansetron, granisetron, dolasetron, palonosetron, and alosetron) is contraindicated .


Probenecid: Probenecid interferes with renal tubular secretion of ciprofloxacin and produces an increase in the level of ciprofloxacin in serum.


Etonogestrel may interact with the following medications: acetaminophen (Tylenol), antibiotics such as ampicillin and tetracycline, anticonvulsants (Dilantin, Phenobarbital, Tegretol, Trileptal, Topamax, Felbatol), antifungals (Gris-PEG, Nizoral, Sporanox), atorvastatin (Lipitor), clofibrate (Atromid-S), cyclosporine (Neoral, Sandimmune), HIV drugs classified as protease inhibitors (Agenerase, Crixivan, Fortovase, Invirase, Kaletra, Norvir, Viracept), morphine (Astramorph, Kadian, MS Contin), phenylbutazone, prednisolone (Prelone), rifadin (rifampin), St. Johns wort, temazepam, theophylline (Theo-Dur), and vitamin C.


Interactions may occur with the following: adrenocorticoids (cortisone-like medicine), anticoagulants (blood thinners), carbamazepine, corticotropin (barbiturates may decrease the effects of these medicines), central nervous system (CNS) depressants (using these medicines with barbiturates may result in increased CNS depressant effects), divalproex sodium, valproic acid (using these medicines with barbiturates may change the amount of either medicine that you need to take), and oral contraceptives containing estrogens (barbiturates may decrease the effectiveness of these oral contraceptives, and you may need to change to a different type of birth control).


Long Acting Nitrates: Nifedipine may be safely co-administered with nitrates, but there have been no controlled studies to evaluate the antianginal effectiveness of this combination.


Antihistamines may enhance the effects of tricyclic antidepressants, barbiturates, alcohol, and other CNS depressants.


However, because bleeding has been reported when ibuprofen and other nonsteroidal anti-inflammatory agents have been administered to patients on coumarin-type anticoagulants, the physician should be cautious when administering ibuprofen to patients on anticoagulants.


Treatment with entacapone coadministered with levodopa/dopa decarboxylase inhibitor does not change these effects.


Binding to Serum Proteins: The following agents may either inhibit levothyroxine sodium binding to serum proteins or alter the concentrations of serum binding proteins: androgens and related anabolic hormones, asparaginase, clofibrate, estrogens and estrogen-containing compounds, 5-fluorouracil, furosemide, glucocorticoids, meclofenamic acid, mefenamic acid, methadone, perphenazine, phenylbutazone, phenytoin, salicylates, tamoxifen.


Azlocillin should not be administered concomitantly with amikacin, ciprofloxacin, gentamicin, netilmicin, or tobramycin.


Although no specific drug interactions with topical glaucoma drugs or systemic medications were identified in clinical studies of IOPIDINE 0.5% Ophthalmic Solution, the possibility of an additive or potentiating effect with CNS depressants (alcohol, barbiturates, opiates, sedatives, anesthetics) should be considered.


Drugs which may enhance the neuromuscular blocking action of TRACRIUM include: enflurane;isoflurane;halothane;certain antibiotics, especially the aminoglycosides and polymyxins;lithium;magnesium salts;procainamide;and quinidine.


Dexamethasone and retinyl acetate similarly inhibit and stimulate EGF- or insulin-induced proliferation of prostatic epithelium.


Sumatriptan - There have been rare postmarketing reports describing patients with weakness, hyperreflexia, and incoordination following the use of a selective serotonin reuptake inhibitor (SSRI) and sumatriptan.


Therefore, the concomitant administration of TRACLEER and glyburide is contraindicated, and alternative hypoglycemic agents should be considered.


Bentiromide may interact with acetaminophen (e.g., Tylenol), chloramphenicol (e.g., Chloromycetin), local anesthetics (e.g., benzocaine and lidocaine), para-aminobenzoic acid (PABA)-containing preparations (e.g., sunscreens and some multivitamins), procainamide (e.g., Pronestyl), sulfonamides (sulfa medicines), thiazide diuretics (use of these medicines during the test period will affect the test results), and pancreatic supplements (use of pancreatic supplements may give false test results).


Quinolones, including nalidixic acid, may enhance the effects of the oral anticoagulant warfarin or its derivatives.


Heparin: Since heparin is contraindicated in patients with heparin-induced thrombocytopenia, the co-administration of Argatroban and heparin is unlikely for this indication.


Iodine or iodine excess may decrease the effect of Carbimazole, and an iodine deficiency can increase the effect of Carbimazole.


The following are examples of substances that may reduce the blood-glucose-lowering effect: corticosteroids, niacin, danazol, diuretics, sympathomimetic agents (e.g., epinephrine, salbutamol, terbutaline), isoniazid, phenothiazine derivatives, somatropin, thyroid hormones, estrogens, progestogens (e.g., in oral contraceptives).


Data suggest that coadministration of oral ketoconazole and cisapride can result in prolongation of the QT interval on the ECG.


The effects of ruthenium red (RR) on inositol 1,4,5-trisphosphate (InsP(3))-induced responses were studied in rat bone marrow megakaryocytes with the patch-clamp whole-cell recording technique in combination with fura-2 microfluorometry.


Clonidine: Concomitant administration of clonidine with agents with b-blocking properties may potentiate blood-pressure- and heart-rate-lowering effects.


Anticholinergics: Concurrent administration of certain anticholinergic compounds, such as belladonna alkaloids and dicyclomine, would be expected to compromise the beneficial effects of cisapride.


The mechanism for this interaction probably is adsorption of nitrofurantoin onto the surface of magnesium trisilicate.


Auranofin should not be used together with penicillamine (Depen, Cuprimine), another arthritis medication.


Anticoagulants, oral: Co-administration of corticosteroids and warfarin usually results in inhibition of response to warfarin, although there have been some conflicting reports.


Inhibitors of this isoenzyme (e.g., macrolide antibiotics, azole antifungal agents, protease inhibitors, serotonin reuptake inhibitors, amiodarone, cannabinoids, diltiazem, grapefruit juice, nefazadone, norfloxacin, quinine, zafirlukast) should be cautiously coadministered with TIKOSYN as they can potentially increase dofetilide levels.


Warfarin: The effect of celecoxib on the anti-coagulant effect of warfarin was studied in a group of healthy subjects receiving daily doses of 2-5 mg of warfarin.


Drug Interactions with Antacids Administration of 120 mg of fexofenadine hydrochloride (2 x 60 mg capsule) within 15 minutes of an aluminum and magnesium containing antacid (Maalox ) decreased fexofenadine AUC by 41% and cmax by 43%.


Dopamine D2 receptor antagonists (e.g., phenothiazines, butyrophenones, risperidone) and isoniazid may reduce the therapeutic effects of levodopa.


Multivalent Cation-Containing Products: Concurrent administration of a quinolone, including ciprofloxacin, with multivalent cation-containing products such as magnesium or aluminum antacids, sucralfate, VIDEX chewable/buffered tablets or pediatric powder, or products containing calcium, iron, or zinc may substantially decrease the absorption of ciprofloxacin, resulting in serum and urine levels considerably lower than desired.


Thus, when NSAIDs and lithium are administered concurrently, subjects should be observed carefully for signs of lithium toxicity.


Chloramphenicol has been shown to be antagonistic to beta-lactam antibiotics, including ceftazidime, based on in vitro studies and time kill curves with enteric gram-negative bacilli.


Close supervision and careful adjustment of dosage are required when Anafranil is administered with anticholinergic or sympathomimetic drugs.


H2 Blockers/Proton Pump Inhibitors: Long-term suppression of gastric acid secretion by H2 blockers or proton pump inhibitors (eg, famotidine and omeprazole) is likely to reduce dasatinib exposure.


Drugs which may enhance the neuromuscular blocking action of TRACRIUM include: enflurane;


Agents that have been found, or are expected to have decreased plasma levels in the presence of EQUETROTM due to induction of CYP enzymes are the following: Acetaminophen, alprazolam, amitriptyline, bupropion, buspirone, citalopram, clobazam, clonazepam, clozapine, cyclosporin, delavirdine, desipramine, diazepam, dicumarol, doxycycline, ethosuximide, felbamate, felodipine, glucocorticoids, haloperidol, itraconazole, lamotrigine, levothyroxine, lorazepam, methadone, midazolam, mirtazapine, nortriptyline, olanzapine, oral contraceptives(3), oxcarbazepine, Phenytoin(4), praziquantel, protease inhibitors, quetiapine, risperidone, theophylline, topiramate, tiagabine, tramadol, triazolam, valproate, warfarin(5) , ziprasidone, and zonisamide.


The following are examples of drugs known to inhibit the metabolism of other related benzodiazepines, presumably through inhibition of CYP3A: nefazodone, fluvoxamine, cimetidine, diltiazem, isoniazide, and some macrolide antibiotics.


Amitriptyline in combination with clonidine enhances the manifestation of corneal lesions in rats Epidural Injection Clonidine may potentiate the CNS-depressive effect of alcohol, barbiturates or other sedating drugs.


Therefore, concurrent use of aspirin and ketoprofen is not recommended.


Limited data in patients receiving known enzyme inducers ( phenytoin, phenobarbital, carbamazepine ) indicate only a 30% increase in the rate of flecainide elimination.