Oxymorphone (oral)

# Disclaimer
WikiDoc MAKES NO GUARANTEE OF VALIDITY. WikiDoc is not a professional health care provider, nor is it a suitable replacement for a licensed healthcare provider.  WikiDoc is intended to be an educational tool, not a tool for any form of healthcare delivery.  The educational content on WikiDoc drug pages is based upon the FDA package insert, National Library of Medicine content and practice guidelines / consensus statements.  WikiDoc does not promote the administration of any medication or device that is not consistent with its labeling. Please read our full disclaimer here.

# Overview
Oxymorphone (oral) is an analgesic opioid that is FDA approved for the {{{indicationType}}} of anesthesia; adjunct, anxiety, Due to dyspnea associated with pulmonary edema caused by acute left ventricular dysfunctionView additional information, obstetric pain, pain, acute (moderate to severe), pain, chronic (severe), in patients requiring daily long-term around-the-clock opioid analgesic, premedication for anesthetic procedure - surgical procedure..   Common adverse reactions include cardiovascular: hypotension (less than 10% ), dermatologic: pruritus (less than or equal to 15.2% ), sweating symptom (1% to less than 10% ), gastrointestinal: abdominal pain (1% to less than 10% ), constipation (4.1% to 27.6% ), nausea (2.9% to 33.1% ), vomiting (less than or equal to 15.6% ), xerostomia (1% to less than 10% ), neurologic: confusion (1% to less than 10% ), dizziness (5% to 17% ), headache (4% to 12% ), somnolence (2% to 19% ), respiratory: dyspnea (1% to less than 10% ), hypoxia (less than 10% ), other: fatigue (1% to less than 10% ), fever (1% to 14.2% ).

# Adult Indications and Dosage

## FDA-Labeled Indications and Dosage (Adult)
- Be aware oxymorphone 5 mg and 10 mg tablets are available as both immediate- and extended-release formulations.
- Do not discontinue abruptly in the physically dependent patient.
- Oral oxymorphone is approximately 10% bioavailable; to convert to parenteral therapy, administer one-tenth the patient's total daily oral oxymorphone dose as the total daily injection dose divided in 4 to 6 doses per day.
- Anesthesia; Adjunct: initially, 1 to 1.5 mg IM or subQ repeated every 4 to 6 hours as needed OR 0.5 mg IV.
- Anxiety, Due to dyspnea associated with pulmonary edema caused by acute left ventricular dysfunction: initially, 1 to 1.5 mg IM or subQ repeated every 4 to 6 hours as needed OR 0.5 mg IV.
- Obstetric pain: 0.5 to 1 mg IM during labor.
- Pain, acute (moderate to severe): (immediate release), initially, 5 to 20 mg orally every 4 to 6 hours; MAX initial: 20 mg/dose; titrate based on patient response.
- Pain, acute (moderate to severe): initially, 1 to 1.5 mg IM or subQ repeated every 4 to 6 hours as needed OR 0.5 mg IV.
- Pain, chronic (severe), in patients requiring daily long-term around-the-clock opioid analgesic: initial dose selection must take into account patient's prior analgesic treatment experience and risk factors for addiction, abuse, and misuse.
- Pain, chronic (severe), in patients requiring daily long-term around-the-clock opioid analgesic: (extended-release) as first opioid analgesic and in patients who are not opioid-tolerant: initiate at 5 mg extended-release orally every 12 hours.
- Pain, chronic (severe), in patients requiring daily long-term around-the-clock opioid analgesic: (conversion from oral immediate-release oxymorphone) administer one-half total daily immediate-release dose orally every 12 hours.
- Pain, chronic (severe), in patients requiring daily long-term around-the-clock opioid analgesic: (conversion from parenteral oxymorphone) administer 5 times the patient's total daily parenteral dose orally every 12 hours and monitor closely due to patient variability.
- Pain, chronic (severe), in patients requiring daily long-term around-the-clock opioid analgesic: (conversion from other oral opioids) underestimate patient's 24-hour oral oxymorphone dose and administer one-half orally every 12 hours while providing rescue medication as needed.
- Pain, chronic (severe), in patients requiring daily long-term around-the-clock opioid analgesic: (extended-release) maintenance: adjust dose of extended-release tablets in increments of 5 to 10 mg orally every 12 hours every 3 to 7 days.
- Premedication for anesthetic procedure - Surgical procedure: initially, 1 to 1.5 mg IM or subQ repeated every 4 to 6 hours as needed OR 0.5 mg IV.

## Off-Label Use and Dosage (Adult)

### Guideline-Supported Use
There is limited information about Off-Label Guideline-Supported Use of Oxymorphone in adult patients.

### NonGuideline-Supported Use
There is limited information about Off-Label NonGuideline-Supported Use of Oxymorphone in adult patients.

# Pediatric Indications and Dosage

## FDA-Labeled Indications and Dosage (Pediatric)
safety and efficacy have not been established in pediatric patients younger than 18 years

## Off-Label Use and Dosage (Pediatric)

### Guideline-Supported Use
There is limited information about Off-Label Guideline-Supported Use of Oxymorphone in pediatric patients.

### NonGuideline-Supported Use
There is limited information about Off-Label NonGuideline-Supported Use of Oxymorphone in pediatric patients.

# Contraindications
- Oxymorphone hydrochloride tablets are contraindicated in patients with a known hypersensitivity to oxymorphone or to any of the other ingredients in oxymorphone hydrochloride tablets, or with known hypersensitivity to morphine analogs such as codeine.
- Oxymorphone hydrochloride tablets are contraindicated in patients with respiratory depression, except in monitored settings and in the presence of resuscitative equipment.
- Oxymorphone hydrochloride tablets are contraindicated in patients with acute or severe bronchial asthma or hypercarbia.
- Oxymorphone hydrochloride tablets are contraindicated in any patient who has or is suspected of having paralytic ileus .
- Oxymorphone hydrochloride tablets are contraindicated in patients with moderate or severe hepatic impairment .

# Warnings
- Respiratory depression is the chief hazard of oxymorphone hydrochloride. Respiratory depression may occur more frequently in elderly or debilitated patients as well as in those suffering from conditions accompanied by hypoxia or hypercapnia, when even moderate therapeutic doses may dangerously decrease pulmonary ventilation.
- Administer oxymorphone hydrochloride with extreme caution to patients with conditions accompanied by hypoxia, hypercapnia, or decreased respiratory reserve such as: asthma, chronic obstructive pulmonary disease or cor pulmonale, severe obesity, sleep apnea syndrome, myxedema, kyphoscoliosis, CNS depression, or coma. In these patients, even usual therapeutic doses of oxymorphone may decrease respiratory drive while simultaneously increasing airway resistance to the point of apnea. Consider alternative non-opioid analgesics and use oxymorphone hydrochloride only under careful medical supervision at the lowest effective dose in such patients.
- Oxymorphone hydrochloride tablets contain oxymorphone, a mu opioid agonist and a Schedule II controlled substance with an abuse liability similar to morphine. Opioid agonists are sought by drug abusers and people with addiction disorders and are subject to criminal diversion.
- Oxymorphone can be abused in a manner similar to other opioid agonists, legal or illicit. This issue should be considered when prescribing or dispensing oxymorphone in situations where the physician or pharmacist is concerned about an increased risk of misuse, abuse, or diversion.
- Oxymorphone hydrochloride tablets may be abused by crushing, chewing, snorting, or injecting the product. These practices pose a significant risk to the abuser that could result in overdose and death .
- Oxymorphone hydrochloride tablets may be targeted for theft and diversion. Healthcare professionals should contact their State Medical Board, State Board of Pharmacy, or State Control Board for information on how to detect or prevent diversion of this product, and security requirements for storing and handling of oxymorphone hydrochloride tablets.
- Healthcare professionals should advise patients to store oxymorphone hydrochloride tablets in a secure place, preferably locked and out of the reach of children and other non-caregivers.
- Concerns about abuse, misuse, diversion and addiction should not prevent the proper management of pain.
- The concomitant use of other CNS depressants including other opioids, general anesthetics, phenothiazines, other tranquilizers, sedatives, hypnotics, and alcohol with oxymorphone may produce increased depressant effects including hypoventilation, hypotension, profound sedation, coma and death .
- In the presence of head injury, intracranial lesions or a preexisting increase in intracranial pressure, the respiratory depressant effects of opioid analgesics and their potential to elevate cerebrospinal fluid pressure (resulting from vasodilation following CO2 retention) may be markedly exaggerated. Furthermore, opioid analgesics can produce effects on papillary response and consciousness, which may obscure neurologic signs of further increases in intracranial pressure in patients with head injuries.
- Administer oxymorphone hydrochloride with extreme caution in patients who may be particularly susceptible to the intracranial effects of CO2 retention, such as those with evidence of increased intracranial pressure or impaired consciousness. Opioids may obscure the clinical course of a patient with a head injury and should be used only if clinically warranted.
- Oxymorphone hydrochloride, like all opioid analgesics, may cause severe hypotension in a patient whose ability to maintain blood pressure has been compromised by a depleted blood volume, or after concurrent administration with drugs such as phenothiazines or other agents that compromise vasomotor tone. Administer oxymorphone hydrochloride with caution to patients in circulatory shock, since vasodilation produced by the drug may further reduce cardiac output and blood pressure.
- A study of extended-release oxymorphone tablets in patients with hepatic disease indicated greater plasma concentrations than in those with normal hepatic function . Use oxymorphone hydrochloride with caution in patients with mild impairment, starting with the lowest dose and titrating slowly while carefully monitoring for side effects . Oxymorphone hydrochloride is contraindicated in patients with moderate or severe hepatic impairment.
- Use oxymorphone hydrochloride with caution in the following conditions: adrenocortical insufficiency (e.g., Addisons disease), prostatic hypertrophy or urethral stricture, severe impairment of pulmonary or renal function, and toxic psychosis.
- Opioids may aggravate convulsions in patients with convulsive disorders, and may induce or aggravate seizures in some clinical settings.
- Opioids diminish propulsive peristaltic waves in the gastrointestinal tract. Monitor for decreased bowel motility in post-operative patients receiving opioids. The administration of oxymorphone hydrochloride may obscure the diagnosis or clinical course in patients with acute abdominal conditions. Oxymorphone hydrochloride is contraindicated in patients with paralytic ileus.
- Oxymorphone hydrochloride, like other opioids, may cause spasm of the sphincter of Oddi and should be used with caution in patients with biliary tract disease, including acute pancreatitis.
- Opioid analgesics impair the mental and physical abilities needed to perform potentially hazardous activities such as driving a car or operating machinery.

# Adverse Reactions

## Clinical Trials Experience
- The following serious adverse reactions are discussed elsewhere in the labeling:
- Respiratory depression 
- Misuse and abuse 
- CNS depressant effects 
- Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice.
- A total of 591 patients were treated with oxymorphone hydrochloride in controlled clinical trials. The clinical trials consisted of patients with acute post-operative pain (n = 557) and cancer pain (n = 34) trials.
- The following table lists adverse reactions that were reported in at least 2% of patients receiving oxymorphone hydrochloride in placebo-controlled trials (acute post-operative pain (N = 557)).
- The common ( 1% to < 10%) adverse drug reactions reported at least once by patients treated with oxymorphone hydrochloride in the clinical trials organized by MedDRAs (Medical Dictionary for Regulatory Activities) System Organ Class were and not represented in Table 1:
- Cardiac disorders: tachycardia
- Gastrointestinal disorders: dry mouth, abdominal distention, and flatulence
- General disorders and administration site conditions: sweating increased
- Nervous system disorders: anxiety and sedation
- Respiratory, thoracic and mediastinal disorders: hypoxia
- Vascular disorders: hypotension
- Other less common adverse reactions known with opioid treatment that were seen < 1% in the oxymorphone hydrochloride trials include the following:
- Abdominal pain, ileus, diarrhea, agitation, disorientation, restlessness, feeling jittery, hypersensitivity, allergic reactions, bradycardia, central nervous system depression, depressed level of consciousness, lethargy, mental impairment, mental status changes, fatigue, depression, clamminess, flushing, hot flashes, dehydration, dermatitis, dyspepsia, dysphoria, edema, euphoric mood, hallucination, hypertension, insomnia, miosis, nervousness, palpitation, postural hypotension, syncope, dyspnea, respiratory depression, respiratory distress, respiratory rate decreased, oxygen saturation decreased, difficult micturition, urinary retention, urticaria, vision blurred, visual disturbances, weakness, appetite decreased, and weight decreased.

## Postmarketing Experience
- The following adverse reactions have been identified during post approval use of oxymorphone hydrochloride. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
- Nervous system disorder: amnesia, convulsion, memory impairment

# Drug Interactions
- Use With CNS Depressants
- The concomitant use of other CNS depressants including sedatives, hypnotics, tranquilizers, general anesthetics, phenothiazines, other opioids, and alcohol may produce additive CNS depressant effects. Oxymorphone hydrochloride, like all opioid analgesics, should be started at 1/3 to 1/2 of the usual dose in patients who are concurrently receiving other central nervous system depressants because respiratory depression, hypotension, and profound sedation, coma and death may result and titrated slowly as necessary for adequate pain relief.
- When combined therapy with any of the above medications is considered, the dose of one or both agents should be reduced .
- Agonist/antagonist analgesics (i.e., pentazocine, nalbuphine, butorphanol, and buprenorphine) should be administered with caution to a patient who has received or is receiving a course of therapy with a pure opioid agonist analgesic such as oxymorphone. In this situation, mixed agonist/antagonist analgesics may reduce the analgesic effect of oxymorphone and/or may precipitate withdrawal symptoms in these patients.
- CNS side effects have been reported (e.g., confusion, disorientation, respiratory depression, apnea, seizures) following coadministration of cimetidine with opioid analgesics; a causal relationship has not been established.
- Anticholinergics or other medications with anticholinergic activity when used concurrently with opioid analgesics may result in increased risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.

### MAO Inhibitors=
- Oxymorphone hydrochloride is not recommended for use in patients who have received MAO inhibitors within 14 days, because severe and unpredictable potentiation by MAO inhibitors has been reported with opioid analgesics. No specific interaction between oxymorphone and monoamine oxidase inhibitors has been observed, but caution in the use of any opioid in patients taking this class of drugs is appropriate.

# Use in Specific Populations

### Pregnancy
Pregnancy Category (FDA): C
- The safety of using oxymorphone in pregnancy has not been established with regard to possible adverse effects on fetal development. The use of oxymorphone hydrochloride in pregnancy, in nursing mothers, or in women of child-bearing potential requires that the possible benefits of the drug be weighted against the possible hazards to the mother and the child.
- Pregnancy Category C
- There are no adequate and well-controlled studies of oxymorphone in pregnant women. In animal studies, oxymorphone caused decreased fetal and pup weights, an increase in stillbirth, and a decrease in postnatal pup survival at maternal oxymorphone doses equivalent to 0.4 to 4 times the human daily dose of 120 mg (based on body surface area). Oxymorphone hydrochloride should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
- In embryo-fetal developmental toxicity studies, pregnant rats and rabbits received oxymorphone hydrochloride at doses up to about 2 times (rats) and 8 times (rabbits) total human daily dose of 120 mg (based on body surface area). No malformations occurred, but reduced fetal weights occurred at maternal doses of 0.8 (rat) and 4 (rabbit) times the total human daily dose of 120 mg (based on body surface area). There were no adverse developmental effects in rats that received 0.4 times or rabbits that received less than 4 times the total human dose. There were no effects of oxymorphone hydrochloride on intrauterine survival at doses in rats  2 times, or in rabbits at  8 times the human dose (see Nonteratogenic Effects, below). In a study conducted prior to the establishment of Good Laboratory Practices (GLP) and not according to current recommended methodology, a single subcutaneous injection of oxymorphone hydrochloride on gestation day 8 produced malformations in offspring of hamsters that received a dose equivalent to 10 times the total human daily dose of 120 mg (based on body surface area). This dose also produced 83% maternal lethality.
- Oxymorphone hydrochloride administration to female rats during gestation in a pre- and postnatal developmental toxicity study reduced mean litter size (18%) at a dose of 25 mg/kg/day, attributed to an increase in the incidence of stillborn pups. An increase in neonatal death occurred at doses  5 mg/kg/day (0.4 times a total human daily dose of 120 mg, based on body surface area). Low pup birth weight, decreased post-natal weight gain, and reduced post-natal survival of pups occurred following treatment of the dams with 25 mg/kg/day (about 2 times a total human daily dose of 120 mg, based on body surface area).
- Prolonged use of opioid analgesics during pregnancy may cause fetal-neonatal physical dependence. Neonatal withdrawal may occur. Symptoms usually appear during the first days of life and may include convulsions, irritability, excessive crying, tremors, hyperactive reflexes, fever, vomiting, diarrhea, sneezing, yawning, and increased respiratory rate.
Pregnancy Category (AUS): 
There is no Australian Drug Evaluation Committee (ADEC) guidance on usage of Oxymorphone (oral) in women who are pregnant.

### Labor and Delivery
- Opioids cross the placenta and may produce respiratory depression in neonates. Oxymorphone hydrochloride is not recommended for use in women during and immediately prior to labor, when use of shorter acting analgesics or other analgesic techniques are more appropriate. Occasionally, opioid analgesics may prolong labor through actions which temporarily reduce the strength, duration, and frequency of uterine contractions. However this effect is not consistent and may be offset by an increased rate of cervical dilatation, which tends to shorten labor. Neonates whose mothers received opioid analgesics during labor should be observed closely for signs of respiratory depression. A specific opioid antagonist, such as naloxone or nalmefene, should be available for reversal of opioid-induced respiratory depression in the neonate.

### Nursing Mothers
- It is not known whether oxymorphone is excreted in human milk. Because many drugs, including some opioids, are excreted in human milk, caution should be exercised when oxymorphone hydrochloride tablets are administered to a nursing woman. Infants exposed to oxymorphone hydrochloride through breast milk should be monitored for excess sedation and respiratory depression. Withdrawal symptoms can occur in breast-fed infants when maternal administration of an opioid analgesic is stopped, or when breast-feeding is stopped.

### Pediatric Use
- Safety and effectiveness of oxymorphone hydrochloride in pediatric patients below the age of 18 years have not been established.

### Geriatic Use
- Oxymorphone hydrochloride should be used with caution in elderly patients .
- Of the total number of subjects in clinical studies of oxymorphone hydrochloride, 31% were 65 and over, while 7% were 75 and over. No overall differences in effectiveness were observed between these subjects and younger subjects. There were several adverse events that were more frequently observed in subjects 65 and over compared to younger subjects. These adverse events included dizziness, somnolence, confusion, and nausea. In general, dose selection for elderly patients should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function, and of concomitant disease or other drug therapy.

### Gender
There is no FDA guidance on the use of Oxymorphone (oral) with respect to specific gender populations.

### Race
There is no FDA guidance on the use of Oxymorphone (oral) with respect to specific racial populations.

### Renal Impairment
- In a study of extended-release oxymorphone tablets, patients with moderate to severe renal impairment were shown to have an increase in bioavailability ranging from 57 to 65% . Such patients should be started cautiously with lower doses of oxymorphone hydrochloride and titrated slowly while monitoring for side effects .

### Hepatic Impairment
- In a study of extended-release oxymorphone tablets, patients with mild hepatic impairment were shown to have an increase in bioavailability of 1.6 fold. Oxymorphone hydrochloride should be used with caution in patients with mild impairment. These patients should be started with the lowest dose and titrated slowly while carefully monitoring for side effects. Oxymorphone hydrochloride is contraindicated for patients with moderate and severe hepatic impairment .

### Females of Reproductive Potential and Males
There is no FDA guidance on the use of Oxymorphone (oral) in women of reproductive potentials and males.

### Immunocompromised Patients
There is no FDA guidance one the use of Oxymorphone (oral) in patients who are immunocompromised.

# Administration and Monitoring

### Administration
There is limited information regarding Oxymorphone (oral) Administration in the drug label.

### Monitoring
There is limited information regarding Oxymorphone (oral) Monitoring in the drug label.

# IV Compatibility
There is limited information regarding the compatibility of Oxymorphone (oral) and IV administrations.

# Overdosage
- Acute overdosage with oxymorphone hydrochloride is characterized by respiratory depression (a decrease in respiratory rate and/or tidal volume, Cheyne-Stokes respiration, cyanosis), extreme somnolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin, constricted pupils, and sometimes bradycardia and hypotension. In some cases, apnea, circulatory collapse, cardiac arrest, and death may occur.
- Oxymorphone hydrochloride may cause miosis, even in total darkness. Pinpoint pupils are a sign of opioid overdose but are not pathognomonic (e.g., pontine lesions of hemorrhagic or ischemic origin may produce similar findings). Marked mydriasis rather than miosis may be seen with hypoxia in overdose situations .
- In the treatment of oxymorphone hydrochloride overdosage, primary attention should be given to the re-establishment of a patent airway and institution of assisted or controlled ventilation. Supportive measures (including oxygen and vasopressors) should be employed in the management of circulatory shock and pulmonary edema accompanying overdose as indicated. Cardiac arrest or arrhythmias may require cardiac massage or defibrillation.
- The opioid antagonist naloxone hydrochloride is a specific antidote against respiratory depression that may result from overdosage or unusual sensitivity to opioids including oxymorphone hydrochloride. Nalmefene is an alternative pure opioid antagonist, which may be administered as a specific antidote to respiratory depression resulting from opioid overdose. Since the duration of action of oxymorphone hydrochloride may exceed that of the antagonist, keep the patient under continued surveillance and administer repeated doses of the antagonist according to the antagonist labeling as needed to maintain adequate respiration.
- In patients receiving oxymorphone hydrochloride, opioid antagonists should not be administered in the absence of clinically significant respiratory or circulatory depression. Administer opioid antagonists cautiously to persons who are known, or suspected to be, physically dependent on any opioid agonist including oxymorphone hydrochloride. In such cases, an abrupt or complete reversal of opioid effects may precipitate an acute abstinence syndrome. In an individual physically dependent on opioids, administration of the usual dose of the antagonist will precipitate an acute withdrawal syndrome. The severity of the withdrawal syndrome produced will depend on the degree of physical dependence and the dose of the antagonist administered. If respiratory depression is associated with muscular rigidity, administration of a neuromuscular blocking agent may be necessary to facilitate assisted or controlled ventilation. Muscular rigidity may also respond to opioid antagonist therapy.

# Pharmacology

## Mechanism of Action
- Oxymorphone, a pure opioid agonist, is relatively selective for the mu receptor, although it can interact with other opioid receptors at higher doses.
- The precise mechanism of analgesia, the principal therapeutic action of oxymorphone, is unknown. Specific CNS opiate receptors and endogenous compounds with morphine-like activity have been identified throughout the brain and spinal cord and are likely to play a role in the expression and perception of analgesic effects.

## Structure
- Oxymorphone hydrochloride is a semi-synthetic opioid analgesic supplied in 5 mg and 10 mg tablet strengths for oral administration. The tablet strengths describe the amount of oxymorphone hydrochloride per tablet. The tablets contain the following inactive ingredients: lactose monohydrate, magnesium stearate, and pregelatinized starch. Additionally, the 5 mg tablets contain FD&C blue #2 aluminum lake; the 10 mg tablets contain FD&C red #40 aluminum lake and FD&C yellow #6 aluminum lake.
- Chemically, oxymorphone hydrochloride is 4, 5-epoxy-3, 14-dihydroxy-17-methylmorphinan-6-one hydrochloride, a white or slightly off-white, odorless powder, which is sparingly soluble in alcohol and ether, but freely soluble in water. The pKa1 and pKa2 of oxymorphone at 37C are 8.17 and 9.54, respectively. The octanol/aqueous partition coefficient at 37C and pH 7.4 is 0.98.
- The structural formula for oxymorphone hydrochloride is as follows:

## Pharmacodynamics
- Pharmacological effects of opioid agonists include analgesia, anxiolysis, euphoria, feelings of relaxation, respiratory depression, constipation, miosis, and cough suppression. Like all pure opioid agonist analgesics, with increasing doses there is increasing analgesia, unlike with mixed agonist/antagonists or non-opioid analgesics, where there is a limit to the analgesic effect with increasing doses. With pure opioid agonist analgesics, there is no defined maximum dose; the ceiling to analgesic effectiveness is imposed only by side effects, the more serious of which may include somnolence and respiratory depression.
- Concentration-Efficacy Relationships
- The minimum effective plasma concentration of oxymorphone for analgesia varies widely among patients, especially among patients who have been previously treated with potent agonist opioids. As a result, individually titrate patients to achieve a balance between therapeutic and adverse effects. The minimum effective analgesic concentration of oxymorphone for any individual patient may increase over time due to an increase in pain, progression of disease, development of a new pain syndrome and/or development of analgesic tolerance.
- Concentration-Adverse Experience Relationships
- There is a general relationship between increasing opioid plasma concentration and increasing frequency of adverse experiences such as nausea, vomiting, CNS effects, and respiratory depression.
- As with all opioids, the dose of oxymorphone hydrochloride must be individualized . The effective analgesic dose for some patients will be too high to be tolerated by other patients.
- The principal therapeutic action of oxymorphone is analgesia. In common with other opioids, oxymorphone causes respiratory depression, in part by a direct effect on the brainstem respiratory centers. The respiratory depression involves a reduction in the responsiveness of the brain stem respiratory centers to both increases in carbon dioxide tension and electrical stimulation. Opioids depress the cough reflex by direct effect on the cough center in the medulla. Antitussive effects may occur with doses lower than those usually required for analgesia. Oxymorphone causes miosis, even in total darkness. Pinpoint pupils are a sign of opioid overdose but are not pathognomonic (e.g., pontine lesions of hemorrhagic or ischemic origin may produce similar findings). Marked mydriasis rather than miosis may be seen with hypoxia in overdose situations . Other therapeutic effects of oxymorphone include anxiolysis, euphoria and feelings of relaxation.
- In addition to analgesia, the widely diverse effects of oxymorphone include drowsiness, changes in mood, decreased gastrointestinal motility, nausea, vomiting, and alterations of the endocrine and autonomic nervous system.
- Gastric, biliary and pancreatic secretions are decreased by oxymorphone. Oxymorphone causes a reduction in motility and is associated with an increase in tone in the antrum of the stomach and duodenum. Digestion of food in the small intestine is delayed and propulsive contractions are decreased. Propulsive peristaltic waves in the colon are decreased, while tone is increased to the point of spasm. The end result may be constipation. Oxymorphone can cause a marked increase in biliary tract pressure as a result of spasm of the sphincter of Oddi; and transient elevations in serum amylase. Oxymorphone may also cause spasm of the sphincter of the urinary bladder.
- Opioids produce peripheral vasodilation which may result in orthostatic hypotension. Release of histamine can occur and may contribute to opioid-induced hypotension. Manifestations of histamine release may include orthostatic hypotension, pruritus, flushing, red eyes, and sweating. Animal studies have shown that oxymorphone has a lower propensity to cause histamine release than other opioids.
- Opioid agonists have been shown to have a variety of effects on the secretion of hormones. Opioids inhibit the secretion of ACTH, cortisol, and luteinizing hormone (LH) in humans. They also stimulate prolactin, growth hormone (GH) secretion, and pancreatic secretion of insulin and glucagon in humans and other species, rats and dogs. Thyroid stimulating hormone (TSH) has been shown to be both inhibited and stimulated by opioids.
- Opioids have been shown to have a variety of effects on components of the immune system in in vitro and animal models. The clinical significance of these findings is unknown.

## Pharmacokinetics

### Absorption
- The absolute oral bioavailability of oxymorphone is approximately 10%. Studies in healthy volunteers reveal predictable relationships between oxymorphone hydrochloride dosage and plasma oxymorphone concentrations.
- Steady-state levels were achieved after three days of multiple dose administration. Under both single-dose and steady-state conditions, dose proportionality has been established for 5 mg, 10 mg and 20 mg doses of oxymorphone hydrochloride, for both peak plasma levels (Cmax) and extent of absorption (AUC)
- NA = not applicable
- After oral dosing with 40 mg of oxymorphone hydrochloride in healthy volunteers under fasting conditions or with a high-fat meal, the Cmax and AUC were increased by approximately 38% in fed subjects relative to fasted subjects. As a result, oxymorphone hydrochloride should be dosed at least one hour prior to or two hours after eating .
- The effect of co-ingestion of alcohol with oxymorphone hydrochloride has not been evaluated. However, an in vivo study was performed to evaluate the effect of alcohol (40%, 20%, 4% and 0%) on the bioavailability of a single dose of 40 mg of extended-release oxymorphone tablets in healthy, fasted volunteers. Following concomitant administration of 240 mL of 40% ethanol the Cmax increased on average by 70% and up to 270% in individual subjects. Following the concomitant administration of 240 mL of 20% ethanol, the Cmax increased on average by 31% and up to 260% in individual subjects. In some individuals there was also a decrease in oxymorphone peak plasma concentrations. No effect on the release of oxymorphone from the extended-release tablet was noted in an in vitro alcohol interaction study. The mechanism of the in vivo interaction is unknown. Therefore, avoid coadministration of oxymorphone and ethanol.
- Formal studies on the distribution of oxymorphone in various tissues have not been conducted. Oxymorphone is not extensively bound to human plasma proteins; binding is in the range of 10% to 12%.
- Oxymorphone is highly metabolized, principally in the liver, and undergoes reduction or conjugation with glucuronic acid to form both active and inactive products. The two major metabolites of oxymorphone are oxymorphone-3-glucuronide and 6-OH-oxymorphone. The mean plasma AUC for oxymorphone-3-glucuronide is approximately 90 fold higher than the parent compound. The pharmacologic activity of the glucuronide metabolite has not been evaluated. 6-OH-oxymorphone has been shown in animal studies to have analgesic bioactivity. The mean plasma 6-OH-oxymorphone AUC is approximately 70% of the oxymorphone AUC following single oral doses but is essentially equivalent to the parent compound at steady-state.
- Because oxymorphone is extensively metabolized, < 1% of the administered dose is excreted unchanged in the urine. On average, 33% to 38% of the administered dose is excreted in the urine as oxymorphone-3-glucuronide and 0.25% to 0.62% is excreted as 6-OH-oxymorphone in subjects with normal hepatic and renal function. In animals given radiolabeled oxymorphone, approximately 90% of the administered radioactivity was recovered within 5 days of dosing. The majority of oxymorphone-derived radioactivity was found in the urine and feces.
- The plasma levels of oxymorphone administered as an extended-release tablet were about 40% higher in elderly ( 65 years of age) than in younger subjects .
- The effect of gender on the pharmacokinetics of oxymorphone hydrochloride has not been studied. In a study with an extended-release formulation of oxymorphone, there was a consistent tendency for female subjects to have slightly higher AUCss and Cmax values than male subjects. However, gender differences were not observed when AUCss and Cmax were adjusted by body weight.
- The liver plays an important role in the pre-systemic clearance of orally administered oxymorphone. Accordingly, the bioavailability of orally administered oxymorphone may be markedly increased in patients with moderate to severe liver disease. The effect of hepatic impairment on the pharmacokinetics of oxymorphone hydrochloride has not been studied. However, in a study with an extended-release formulation of oxymorphone, the disposition of oxymorphone was compared in 6 patients with mild, 5 patients with moderate, and one patient with severe hepatic impairment, and 12 subjects with normal hepatic function. The bioavailability of oxymorphone was increased by 1.6 fold in patients with mild hepatic impairment and by 3.7 fold in patients with moderate hepatic impairment. In one patient with severe hepatic impairment, the bioavailability was increased by 12.2 fold. The half-life of oxymorphone was not significantly affected by hepatic impairment.
- The effect of renal impairment on the pharmacokinetics of oxymorphone hydrochloride has not been studied. However, in a study with an extended-release formulation of oxymorphone, an increase of 26%, 57%, and 65% in oxymorphone bioavailability was observed in mild (creatinine clearance 51 to 80 mL/min; n = 8), moderate (creatinine clearance 30 to 50 mL/min; n = 8), and severe (creatinine clearance < 30 mL/min; n = 8) patients, respectively, compared to healthy controls.
- In vitro studies revealed little to no biotransformation of oxymorphone to 6-OH-oxymorphone by any of the major cytochrome P450 (CYP P450) isoforms at therapeutically relevant oxymorphone plasma concentrations.
- No inhibition of any of the major CYP P450 isoforms was observed when oxymorphone was incubated with human liver microsomes at concentrations of  50 M. An inhibition of CYP 3A4 activity occurred at oxymorphone concentrations  150 M. Therefore, it is not expected that oxymorphone, or its metabolites will act as inhibitors of any of the major CYP P450 enzymes in vivo.
- Increases in the activity of the CYP 2C9 and CYP 3A4 isoforms occurred when oxymorphone was incubated with human hepatocytes. However, clinical drug interaction studies with oxymorphone hydrochloride extended-release tablets showed no induction of CYP450 3A4 or 2C9 enzyme activity, indicating that no dose adjustment for CYP 3A4- or 2C9-mediated drug-drug interactions is required.

## Nonclinical Toxicology
- Long-term studies have been completed to evaluate the carcinogenic potential of oxymorphone in both Sprague-Dawley rats and CD-1 mice. Oxymorphone was administered to Sprague-Dawley rats (2.5, 5, and 10 mg/kg/day in males and 5, 10, and 25 mg/kg/day in females) for 2 years by oral gavage. The systemic drug exposure (AUC ngh/mL) at the 10 mg/kg/day dose in male rats was 0.34 fold and at the 25 mg/kg/day dose in female rats was 1.5 fold the human exposure at a dose of 260 mg/day. No evidence of carcinogenic potential was observed in rats. Oxymorphone was administered to CD-1 mice (10, 25, 75 and 150 mg/kg/day) for 2 years by oral gavage. The systemic drug exposure (AUC ngh/mL) at the 150 mg/kg/day dose in mice was 14.5 fold (in males) and 17.3 fold (in females) times the human exposure at a dose of 260 mg/day. No evidence of carcinogenic potential was observed in mice.
- Oxymorphone hydrochloride was not mutagenic when tested in the in vitro bacterial reverse mutation assay (Ames test) at concentrations of  5270 mcg/plate, or in an in vitro mammalian cell chromosome aberration assay performed with human peripheral blood lymphocytes at concentrations  5000 mcg/ml with or without metabolic activation. Oxymorphone hydrochloride tested positive in both the rat and mouse in vivo micronucleus assays. An increase in micronucleated polychromatic erythrocytes occurred in mice given doses of  250 mg/kg and in rats given doses of 20 and 40 mg/kg. A subsequent study demonstrated that oxymorphone hydrochloride was not aneugenic in mice following administration of up to 500 mg/kg. Additional studies indicate that the increased incidence of micronucleated polychromatic erythrocytes in rats may be secondary to increased body temperature following oxymorphone administration. Doses associated with increased micronucleated polychromatic erythrocytes also produce a marked, rapid increase in body temperature. Pretreatment of animals with sodium salicylate minimized the increase in body temperature and prevented the increase in micronucleated polychromatic erythrocytes after administration of 40 mg/kg oxymorphone.
- Oxymorphone did not affect reproductive function or sperm parameters in male rats at any dose tested ( 50 mg/kg/day). In female rats, an increase in the length of the estrus cycle and decrease in the mean number of viable embryos, implantation sites and corpora lutea were observed at doses of oxymorphone  10 mg/kg/day. The dose of oxymorphone associated with reproductive findings in female rats is 0.8 times a total human daily dose of 120 mg based on a body surface area. The dose of oxymorphone that produced no adverse effects on reproductive findings in female rats (i.e., NOAEL) is 0.4 times a total human daily dose of 120 mg based on body surface area.

# Clinical Studies
- The analgesic efficacy of oxymorphone hydrochloride has been evaluated in acute pain following orthopedic and abdominal surgeries.
- Two double-blind, placebo-controlled, dose-ranging studies in patients with acute moderate to severe pain following orthopedic surgery evaluated the doses of oxymorphone hydrochloride 10 mg and 20 mg, and 30 mg was included in one study. Both studies demonstrated that oxymorphone hydrochloride 20 mg provided greater analgesia as measured by total pain relief based on a weighted analysis over 8 hours using a 0 to 4 categorical, compared to placebo. Oxymorphone hydrochloride 10 mg provided greater analgesia as compared to placebo in one of the two studies. There was no evidence of superiority of the 30 mg dose over the 20 mg dose. However, there was a high rate of naloxone use in patients receiving the oxymorphone hydrochloride 30 mg dose in the post-operative period .
- In a randomized, double-blind, placebo-controlled, multiple-dose study, the efficacy of oxymorphone hydrochloride 10 mg and 20 mg was assessed in patients with moderate to severe acute pain following abdominal surgery. In this study, patients were dosed every 4 to 6 hours over a 48 hour treatment period. Oxymorphone hydrochloride 10 and 20 mg provided greater analgesia, as measured by the mean average pain intensity on a 0 to 100 mm visual analog scale, over 48 hours, compared to placebo .

# How Supplied
- Oxymorphone hydrochloride tablets are supplied as follows:

## Storage
- Store at 20 to 25C (68 to 77F) .
- KEEP THIS AND ALL MEDICATIONS OUT OF THE REACH OF CHILDREN.

# Images

## Drug Images

## Package and Label Display Panel

# Patient Counseling Information
- Advise patients that oxymorphone hydrochloride tablets contain oxymorphone, which is a morphine-like pain reliever, and should be taken only as directed.
- Advise patients that oxymorphone hydrochloride tablets are a potential drug of abuse. They should protect them from theft, and they should never be given to anyone other than the individual for whom it was prescribed.
- Advise patients to keep oxymorphone hydrochloride tablets in a secure place out of the reach of children and pets. Accidental consumption especially in children may result in overdose or death. When oxymorphone hydrochloride tablets are no longer needed, the unused tablets should be destroyed by flushing down the toilet.
- Advise patients to report episodes of breakthrough pain and adverse experiences occurring during therapy to their doctor. Individualization of dosage is essential to make optimal use of this medication.
- Advise patients not to adjust the dose of oxymorphone hydrochloride tablets without consulting the prescriber.
- Advise patients that oxymorphone hydrochloride tablets may cause drowsiness, dizziness, or lightheadedness and may impair mental and/or physical abilities required for the performance of potentially hazardous tasks, such as driving a car, operating machinery, etc.
- Advise patients that oxymorphone hydrochloride tablets will add to the effect of alcohol and other CNS depressants (such as antihistamines, sedatives, hypnotics, tranquilizers, general anesthetics, phenothiazines, other opioids, and monoamine oxidase  inhibitors).
- Advise patients not to combine oxymorphone hydrochloride tablets with alcohol or other central nervous system depressants (sleep aids, tranquilizers) except by the orders of the prescribing physician, because dangerous additive effects may occur, resulting in serious injury or death.
- Advise patients of the potential for severe constipation. Appropriate laxatives and/or stool softeners and other therapeutic approaches should be considered for use with the initiation of oxymorphone hydrochloride tablet therapy.
- Advise women of childbearing potential who become or are planning to become pregnant to consult their physician regarding the effects of opioid analgesics and other drug use during pregnancy on themselves and their unborn child.
- Advise women of childbearing potential who become or are planning to become pregnant that safe use in pregnancy has not been established. Prolonged use of opioid analgesics during pregnancy may cause fetal-neonatal physical dependence, and neonatal withdrawal may occur.
- Advise patients that if they have been receiving treatment with oxymorphone hydrochloride tablets for more than a few weeks and cessation of therapy is indicated, it may be appropriate to taper the oxymorphone hydrochloride tablet dose, rather than abruptly discontinue it, due to the risk of precipitating withdrawal symptoms. Their physician can provide a dose schedule to accomplish a gradual discontinuation of the medication.

# Precautions with Alcohol
Alcohol-Oxymorphone interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.

# Brand Names
There is limited information regarding Oxymorphone (oral) Brand Names in the drug label.

# Look-Alike Drug Names
There is limited information regarding Oxymorphone (oral) Look-Alike Drug Names in the drug label.

# Drug Shortage Status

# Price