The active components in Ipratropium Bromide and Albuterol Sulfate Inhalation Solution are albuterol sulfate and ipratropium bromide. Albuterol sulfate is a salt of racemic albuterol and a relatively selective β​2-adrenergic bronchodilator chemically described as α1 -[(tert-Butylamino) methyl]-4-hydroxy-m-xylene- α,α′-diol sulfate (2:1) (salt). It has a molecular weight of 576.7 and the empirical formula is (C13 H21 NO3)2 • H2SO4 . It is a white crystalline powder, soluble in water and slightly soluble in ethanol. The World Health Organization’s recommended name for albuterol base is salbutamol.

Ipratropium bromide is an anticholinergic bronchodilator chemically described as 8-azoniabicyclo[3.2.1]-octane,3-(3-hydroxy-1-oxo-2-phenylpropoxy)-8-methyl-8-(1-methylethyl)-,bromide, monohydrate (endo,syn)-, (±)-; a synthetic quaternary ammonium compound, chemically related to atropine. It has a molecular weight of 430.4 and the empirical formula is C​20H​30BrNO​3 • H​2O. It is a white crystalline substance, freely soluble in water and lower alcohols, and insoluble in lipophilic solvents such as ether, chloroform, and fluorocarbons.

Each 3 mL vial of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution contains 3 mg (0.1%) of albuterol sulfate (equivalent to 2.5 mg (0.083%) of albuterol base) and 0.5 mg (0.017%) of ipratropium bromide in an isotonic, sterile, aqueous solution containing sodium chloride and hydrochloric acid to adjust to pH 4. Ipratropium Bromide and Albuterol Sulfate Inhalation Solution is a clear, colorless solution. It does not require dilution prior to administration by nebulization. For Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, like all other nebulized treatments, the amount delivered to the lungs will depend on patient factors, the jet nebulizer utilized, and compressor performance. Using the Pari-LC-Plus™ nebulizer (with face mask or mouthpiece) connected to a PRONEB™ compressor system, under in vitro conditions, the mean delivered dose from the mouth piece (% nominal dose) was approximately 46% of albuterol and 42% of ipratropium bromide at a mean flow rate of 3.6 L/min. The mean nebulization time was 15 minutes or less. Ipratropium Bromide and Albuterol Sulfate Inhalation Solution should be administered from jet nebulizers at adequate flow rates, via face masks or mouthpieces (see DOSAGE AND ADMINISTRATION).

CLINICAL PHARMACOLOGY Ipratropium Bromide and Albuterol Sulfate Inhalation Solution is a combination of the β​2-adrenergic bronchodilator, albuterol sulfate, and the anticholinergic bronchodilator, ipratropium bromide.

Albuterol sulfate: Mechanism of Action:​ The prime action of β-adrenergic drugs is to stimulate adenyl cyclase, the enzyme that catalyzes the formation of cyclic-3’,5’-adenosine monophosphate (cAMP) from adenosine triphosphate (ATP). The cAMP thus formed mediates the cellular responses. In vitro studies and in vivo pharmacologic studies have demonstrated that albuterol has a preferential effect on β​2-adrenergic receptors compared with isoproterenol. While it is recognized that β​2-adrenergic receptors are the predominant receptors in bronchial smooth muscle, recent data indicated that 10% to 50% of the β-receptors in the human heart may be β​2-receptors. The precise function of these receptors, however, is not yet established. Albuterol has been shown in most controlled clinical trials to have more effect on the respiratory tract, in the form of bronchial smooth muscle relaxation, than isoproterenol at comparable doses while producing fewer cardiovascular effects. Controlled clinical studies and other clinical experience have shown that inhaled albuterol, like other β-adrenergic agonist drugs, can produce a significant cardiovascular effect in some patients.

Pharmacokinetics: Albuterol sulfate is longer acting than isoproterenol in most patients by any route of administration, because it is not a substrate for the cellular uptake processes for catecholamines nor for the metabolism of catechol-O-methyl transferase. Instead the drug is conjugatively metabolized to albuterol 4’-O-sulfate.

Animal Pharmacology/Toxicology: Intravenous studies in rats with albuterol sulfate have demonstrated that albuterol crosses the blood-brain barrier and reaches brain concentrations amounting to approximately 5% of plasma concentrations. In structures outside of the blood-brain barrier (pineal and pituitary glands), albuterol concentrations were found to be 100 times those found in whole brain. Studies in laboratory animals (minipigs, rodents, and dogs) have demonstrated the occurrence of cardiac arrythmias and sudden death (with histological evidence of myocardial necrosis) when beta-agonists and methylxanthines are administered concurrently. The clinical significance of these findings is unknown.

Ipratropium bromide: Mechanism of Action: ​Ipratropium bromide is an anticholinergic (parasympatholytic) agent, which blocks the muscarinic receptors of acetylcholine, and, based on animal studies, appears to inhibit vagally mediated reflexes by antagonizing the action of acetylcholine, the transmitter agent released from the vagus nerve. Anticholinergics prevent the increases in intracellular concentration of cyclic guanosine monophosphate (cGMP), resulting from the interaction of acetylcholine with the muscarinic receptors of bronchial smooth muscle.

Pharmacokinetics: The bronchodilation following inhalation of ipratropium is primarily a local, site-specific effect, not a systemic one. Much of an inhaled dose is swallowed as shown by fecal excretion studies. Following nebulization of a 1 mg dose to healthy volunteers, a mean of 4% of the dose was excreted unchanged in the urine. Ipratropium bromide is minimally (0% to 9% in vitro) bound to plasma albumin and α​1–acid glycoproteins. It is partially metabolized to inactive ester hydrolysis products. Following intravenous administration, approximately one-half is excreted unchanged in the urine. The half-life of elimination is about 1.6 hours after intravenous administration. Ipratropium bromide that reaches the systemic circulation is reportedly removed by the kidneys rapidly at a rate that exceeds the glomerular filtration rate. The pharmacokinetics of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution or ipratropium bromide have not been studied in the elderly and in patients with hepatic or renal insufficiency (see PRECAUTIONS).

Animal Pharmacology/Toxicology:  Autoradiographic studies in rats have shown that ipratropium does not penetrate the blood-brain barrier.

Ipratropium Bromide and Albuterol Sulfate Inhalation Solution: Mechanism of Action: Ipratropium Bromide and Albuterol Sulfate Inhalation Solution is expected to maximize the response to treatment in patients with chronic obstructive pulmonary disease (COPD) by reducing bronchospasm through two distinctly different mechanisms: sympathomimetic (albuterol sulfate) and anticholinergic / parasympatholytic (ipratropium bromide). Simultaneous administration of both an anticholinergic and a β​2-sympathomimetic is designed to produce greater bronchodilation effects than when either drug is utilized alone at its recommended dosage.

Animal Pharmacology/Toxicology: In 30-day studies in Sprague-Dawley rats and Beagle dogs, subcutaneous doses of up to 205.5 mcg/kg of ipratropium administered with up to 1000 mcg/kg albuterol in rats and 3.16 mcg/kg ipratropium and 15 mcg/kg albuterol in dogs (less than the maximum recommended daily inhalation dose for adults on a mg/m​2 basis) did not cause death or potentiation of the cardiotoxicity induced by albuterol administered alone.

​Pharmacokinetics: In a double-blind, double period, crossover study, 15 male and female subjects were administered single doses of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution or albuterol sulfate inhalation solution at two times the recommended single doses as two inhalations separated by 15 minutes. The total nebulized dose of albuterol sulfate from both treatments was 6 mg and the total dose of ipratropium bromide from Ipratropium Bromide and Albuterol Sulfate Inhalation Solution was 1 mg. Peak albuterol plasma concentrations occurred at 0.8 hours after dosing for both treatments. The mean peak albuterol concentration following administration of albuterol sulfate alone was 4.86 (±2.65) ng/mL and it was 4.65 (± 2.92) ng/mL for Ipratropium Bromide and Albuterol Sulfate Inhalation Solution. Mean AUC values for the two treatments were 26.6 (± 15.2) ng•hr/mL (albuterol sulfate alone) versus 24.2 (± 14.5) ng•hr/mL (Ipratropium Bromide and Albuterol Sulfate Inhalation Solution). The mean t​1/2 values were 7.2 (± 1.3) hours (albuterol sulfate alone) and 6.7 (± 1.7) hours (Ipratropium Bromide and Albuterol Sulfate Inhalation Solution). A mean of 8.4 (± 8.9)% of the albuterol dose was excreted unchanged in urine following administration of two vials of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution which is similar to 8.8 (± 7.3)% that was obtained from albuterol sulfate inhalation solution. There were no statistically significant differences in the pharmacokinetics of albuterol between the two treatments. For ipratropium, a mean of 3.9 (± 5.1)% of the ipratropium bromide dose was excreted unchanged in the urine following two vials of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, which is comparable with previously reported data.

​Clinical Trials: ​In a 12-week, randomized, double-blind, positive-control, crossover study of albuterol sulfate, ipratropium bromide and Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, 863 COPD patients were evaluated for bronchodilator efficacy comparing Ipratropium Bromide and Albuterol Sulfate Inhalation Solution with albuterol sulfate and ipratropium bromide alone.

Ipratropium Bromide and Albuterol Sulfate Inhalation Solution demonstrated significantly better changes in FEV1, as measured from the baseline to peak response, when compared with either albuterol sulfate or ipratropium bromide. Ipratropium Bromide and Albuterol Sulfate Inhalation Solution was also shown to have the rapid onset associated with albuterol sulfate, with a mean time to peak FEV﻿1 of 1.5 hours, and the extended duration associated with ipratropium bromide with a duration of 15% response in FEV​1 of 4.3 hours.

This study demonstrated that each component of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution contributed to the improvement in pulmonary function, especially during the first 4 to 5 hours after dosing, and that Ipratropium Bromide and Albuterol Sulfate Inhalation Solution was significantly more effective than albuterol sulfate or ipratropium bromide alone.

INDICATIONS AND USAGE Ipratropium Bromide and Albuterol Sulfate Inhalation Solution is indicated for the treatment of bronchospasm associated with COPD in patients requiring more than one bronchodilator.

CONTRAINDICATIONS Ipratropium Bromide and Albuterol Sulfate Inhalation Solution is contraindicated in patients with a history of hypersensitivity to any of its components, or to atropine and its derivatives.

WARNINGS Paradoxical Bronchospasm: In the clinical study of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, paradoxical bronchospasm was not observed. However, paradoxical bronchospasm has been observed with both inhaled ipratropium bromide and albuterol products and can be life-threatening. If this occurs, Ipratropium Bromide and Albuterol Sulfate Inhalation Solution should be discontinued immediately and alternative therapy instituted.

Do Not Exceed Recommended Dose: Fatalities have been reported in association with excessive use of inhaled products containing sympathomimetic amines and with the home use of nebulizers.

Cardiovascular Effect: Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, like other beta-adrenergic agonists, can produce a clinically significant cardiovascular effect in some patients as measured by pulse rate, blood pressure, and/or symptoms. Although such effects are uncommon for Ipratropium Bromide and Albuterol Sulfate Inhalation Solution at recommended doses, if they occur, the drug may need to be discontinued. In addition, beta-agonists have been reported to produce ECG changes, such as flattening of the T-wave, prolongation of the QTc interval, and ST segment depression. The clinical significance of these findings is unknown. Therefore, Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, like other sympathomimetic amines, should be used with caution in patients with cardiovascular disorders, especially coronary insufficiency, cardiac arrhythmias, and hypertension.

Immediate Hypersensitivity Reactions: Immediate hypersensitivity reactions to albuterol and/or ipratropium bromide may occur after the administration of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution as demonstrated by rare cases of urticaria, angioedema, rash, pruritus, oropharyngeal edema, bronchospasm, and anaphylaxis.

PRECAUTIONS General 1\. Effects Seen with Sympathomimetic Drugs: ​​As with all products containing sympathomimetic amines, Ipratropium Bromide and Albuterol Sulfate Inhalation Solution should be used with caution in patients with cardiovascular disorders, especially coronary insufficiency, cardiac arrhythmias, and hypertension; in patients with convulsive disorders, hyperthyroidism, or diabetes mellitus; and in patients who are unusually responsive to sympathomimetic amines. Large doses of intravenous albuterol have been reported to aggravate pre-existing diabetes mellitus and ketoacidosis. Additionally, β-agonists may cause a decrease in serum potassium in some patients, possibly through intracellular shunting. The decrease is usually transient, not requiring supplementation.

2\. Effects Seen with Anticholinergic Drugs: Due to the presence of ipratropium bromide in Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, it should be used with caution in patients with narrow-angle glaucoma, prostatic hypertrophy, or bladder-neck obstruction.

3\. Use in Hepatic or Renal Diseases: Ipratropium Bromide and Albuterol Sulfate Inhalation Solution has not been studied in patients with hepatic or renal insufficiency. It should be used with caution in these patient populations.

Information for Patients: The action of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution should last up to 5 hours. Ipratropium Bromide and Albuterol Sulfate Inhalation Solution should not be used more frequently than recommended. Patients should be instructed not to increase the dose or frequency of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution without consulting their healthcare provider. If symptoms worsen, patients should be instructed to seek medical consultation. Patients must avoid exposing their eyes to this product as temporary pupillary dilation, blurred vision, eye pain, or precipitation or worsening of narrow-angle glaucoma may occur, and therefore proper nebulizer technique should be assured, particularly if a mask is used. If a patient becomes pregnant or begins nursing while on Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, they should contact their healthcare provider about use of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution. 

See the illustrated Patient’s Instruction for Use in the product package insert.

Drug Interactions Anticholinergic agents: Although ipratropium bromide is minimally absorbed into the systemic circulation, there is some potential for an additive interaction with concomitantly used anticholinergic medications. Caution is, therefore, advised in the co-administration of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution with other drugs having anticholinergic properties.

β-adrenergic agents: Caution is advised in the co-administration of Ipratropium Bromide and Albuterol Sulfate Inhalation Solution and other sympathomimetic agents due to the increased risk of adverse cardiovascular effects.

β-receptor blocking agents: These agents and albuterol sulfate inhibit the effect of each other. β-receptor blocking agents should be used with caution in patients with hyperreactive airways, and if used, relatively selective β​1 selective agents are recommended.

Diuretics: The electrocardiogram (ECG) changes and/or hypokalemia that may result from the administration of non-potassium sparing diuretics (such as loop or thiazide diuretics) can be acutely worsened by β-agonists, especially when the recommended dose of the β-agonist is exceeded. Although the clinical significance of these effects is not known, caution is advised in the co-administration of β-agonist containing drugs, such as Ipratropium Bromide and Albuterol Sulfate Inhalation Solution, with non-potassium sparing diuretics.

Monoamine oxidase inhibitors or tricyclic antidepressants: Ipratropium Bromide and Albuterol Sulfate Inhalation Solution should be administered with extreme caution to patients being treated with monoamine oxidase inhibitors or tricyclic antidepressants, or within 2 weeks of discontinuation of such agents because the action of albuterol sulfate on the cardiovascular system may be potentiated.