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Medication Safety Issues
Sound-alike/look-alike issues:
Oxazepam may be confused with oxaprozin, quazepam
Serax® may be confused with Eurax®, Urex®, Zyrtec®
International issues:
Murelax® [Australia] may be confused with Miralax™ which is a brand name for polyethylene glycol 3350 in the U.S.
Pronunciation
(oks A ze pam)
U.S. Brand Names
Generic Available
Yes: Capsule
Canadian Brand Names
Pharmacologic Category
Use: Labeled Indications
Treatment of anxiety; management of ethanol withdrawal
Use: Unlabeled/Investigational
Anticonvulsant in management of simple partial seizures; hypnotic
Restrictions
C-IV
Pregnancy Risk Factor
D
Lactation
Enters breast milk/not recommended
Contraindications
Hypersensitivity to oxazepam or any component of the formulation (cross-sensitivity with other benzodiazepines may exist); narrow-angle glaucoma (not in product labeling, however, benzodiazepines are contraindicated); not indicated for use in the treatment of psychosis; pregnancy
Warnings/Precautions
Concerns related to adverse effects:
• Anterograde amnesia: Benzodiazepines have been associated with anterograde amnesia.
• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving).
• Hypotension: May cause hypotension (rare); use with caution in patients with cardiovascular or cerebrovascular disease, or in patients who would not tolerate transient decreases in blood pressure.
• Paradoxical reactions: Paradoxical reactions, including hyperactive or aggressive behavior, have been reported with benzodiazepines, particularly in adolescent/pediatric or psychiatric patients.
Disease-related concerns:
• Depression: Use caution in patients with depression, particularly if suicidal risk may be present.
• Drug abuse: Use with caution in patients with a history of drug abuse or acute alcoholism; potential for drug dependency exists. Tolerance, psychological and physical dependence may occur with prolonged use.
• Hepatic impairment: Use with caution in patients with hepatic impairment.
• Impaired gag reflux: Use with caution in patients with an impaired gag reflux.
• Renal impairment: Use with caution in patients with renal impairment.
• Respiratory disease: Use with caution in patients with respiratory disease.
Concurrent drug therapy issues:
• CNS depressants/psychoactive medications: Use with caution in patients receiving other CNS depressants or psychoactive medication; effects with other sedative drugs or ethanol may be potentiated.
Special populations:
• Debilitated patients: Use with caution in debilitated patients.
• Elderly: Use with caution in the elderly; benzodiazepines have been associated with falls and traumatic injury.
• Fall risk: Use with extreme caution in patients who are at risk of falls; benzodiazepines have been associated with falls and traumatic injury.
• Pediatrics: Safety and efficacy in established in pediatric patients <6 years of age; dose has not been established between 6-12 years of age.
Dosage form specific issues:
• Tartrazine: Serax® 15 mg tablet contains tartrazine.
Other warnings/precautions:
• Appropriate use: Does not have analgesic, antidepressant, or antipsychotic properties.
• Withdrawal: Rebound or withdrawal symptoms may occur following abrupt discontinuation or large decreases in dose. Use caution when reducing dose or withdrawing therapy; decrease slowly and monitor for withdrawal symptoms. Flumazenil may cause withdrawal in patients receiving long-term benzodiazepine therapy.
Adverse Reactions
Frequency not defined.
Cardiovascular: Syncope (rare), edema
Central nervous system: Drowsiness, ataxia, dizziness, vertigo, memory impairment, headache, paradoxical reactions (excitement, stimulation of effect), lethargy, amnesia, euphoria
Dermatologic: Rash
Endocrine & metabolic: Decreased libido, menstrual irregularities
Genitourinary: Incontinence
Hematologic: Leukopenia, blood dyscrasias
Hepatic: Jaundice
Neuromuscular & skeletal: Dysarthria, tremor, reflex slowing
Ocular: Blurred vision, diplopia
Miscellaneous: Drug dependence
Drug Interactions
Alcohol (Ethyl): CNS Depressants may enhance the CNS depressant effect of Alcohol (Ethyl). Risk C: Monitor therapy
Clozapine: Benzodiazepines may enhance the adverse/toxic effect of Clozapine. Risk D: Consider therapy modification
CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants. Risk C: Monitor therapy
Phenytoin: Benzodiazepines may increase the serum concentration of Phenytoin. Short-term exposure to benzodiazepines may not present as much risk as chronic therapy. Risk C: Monitor therapy
Theophylline Derivatives: May diminish the therapeutic effect of Benzodiazepines. Risk D: Consider therapy modification
Ethanol/Nutrition/Herb Interactions
Ethanol: Avoid ethanol (may increase CNS depression).
Herb/Nutraceutical: Avoid valerian, St John's wort, kava kava, gotu kola (may increase CNS depression).
Mechanism of Action
Binds to stereospecific benzodiazepine receptors on the postsynaptic GABA neuron at several sites within the central nervous system, including the limbic system, reticular formation. Enhancement of the inhibitory effect of GABA on neuronal excitability results by increased neuronal membrane permeability to chloride ions. This shift in chloride ions results in hyperpolarization (a less excitable state) and stabilization.
Pharmacodynamics/Kinetics
Absorption: Almost complete
Protein binding: 86% to 99%
Metabolism: Hepatic to inactive compounds (primarily as glucuronides)
Half-life elimination: 2.8-5.7 hours
Time to peak, serum: 2-4 hours
Excretion: Urine (as unchanged drug (50%) and metabolites)
Dosage
Oral:
Adults:
Anxiety: 10-30 mg 3-4 times/day
Ethanol withdrawal: 15-30 mg 3-4 times/day
Hypnotic: 15-30 mg
Elderly: Oral: Anxiety: 10 mg 2-3 times/day; increase gradually as needed to a total of 30-45 mg/day. Dose titration should be slow to evaluate sensitivity.
Hemodialysis: Not dialyzable (0% to 5%)
Administration: Oral
Give orally in divided doses
Monitoring Parameters
Respiratory and cardiovascular status
Reference Range
Therapeutic: 0.2-1.4 mcg/mL (SI: 0.7-4.9 ?mol/L)
Patient Education
Take exactly as directed; do not increase dose or frequency. It may take 2-3 weeks to achieve desired results. Drug may cause physical and/or psychological dependence. Do not use alcohol or other prescription or OTC medications (especially pain medications, sedatives, antihistamines, or hypnotics) without consulting prescriber. Maintain adequate hydration (2-3 L/day of fluids) unless instructed to restrict fluid intake. You may experience drowsiness, lightheadedness, impaired coordination, dizziness, or blurred vision (use caution when driving or engaging in tasks requiring alertness until response to drug is known); nausea, vomiting, or dry mouth (small frequent meals, frequent mouth care, chewing gum, or sucking lozenges may help); constipation (increased exercise, fluids, fruit, or fiber may help); altered sexual drive or ability (reversible); or photosensitivity (use sunscreen, wear protective clothing and eyewear, and avoid direct sunlight). Report persistent CNS effects (eg, confusion, depression, thoughts of suicide, increased sedation, excitation, headache, agitation, insomnia or nightmares, dizziness, fatigue, impaired coordination, changes in personality, or changes in cognition); changes in urinary pattern; muscle cramping, weakness, tremors, or rigidity; ringing in ears or visual disturbances; chest pain, palpitations, or rapid heartbeat; excessive perspiration, excessive GI symptoms (cramping, constipation, vomiting, anorexia); or worsening of condition. Pregnancy/breast-feeding precautions: Do not get pregnant while taking this medication; use appropriate contraceptive measures. Breast-feeding is not recommended.
Geriatric Considerations
Because of its relatively short half-life and its lack of active metabolites, oxazepam is recommended for use in the elderly when a benzodiazepine is indicated.
Additional Information
Not intended for management of anxieties and minor distresses associated with everyday life. Treatment longer than 4 months should be re-evaluated to determine the patient's need for the drug. Abrupt discontinuation after sustained use (generally >10 days) may cause withdrawal symptoms.
Anesthesia and Critical Care Concerns/Other Considerations
Not intended for management of anxieties and minor distresses associated with everyday life; treatment >4 months should be re-evaluated to determine the patient's need for the drug. Chronic use of this agent may increase the perioperative benzodiazepine dose needed to achieve desired effect. Abrupt discontinuation after sustained use (generally >10 days) may cause withdrawal symptoms.
Dental Health: Effects on Dental Treatment
Key adverse event(s) related to dental treatment: Xerostomia (normal salivary flow resumes upon discontinuation).
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Mental Health: Comment
There are two subtypes of GABA receptors (GABA-A and GABA-B) and three different benzodiazepine receptors (Bz1, Bz2, and Bz3). Benzodiazepine receptors and effects appear to be linked to the GABA-A receptors. Benzodiazepines do not bind to GABA-B receptors. The role of GABA-B receptors is unclear. Benzodiazepines have no specificity for benzodiazepine receptor subtypes.
Oxazepam is a short half-life benzodiazepine. Duration of action after a single dose is determined by redistribution rather than metabolism. Tolerance develops to the sedative, hypnotic, and anticonvulsant effects. It does not develop to the anxiolytic or skeletal muscle relaxing effects. Psychological and physical dependence may occur with prolonged use of benzodiazepines. The onset of withdrawal symptoms is usually seen on the first day without drug and lasts 5-7 days in patients receiving short half-life benzodiazepines, whereas, the onset occurs after 5 days with a duration of 10-14 days after abrupt discontinuance of long half-life benzodiazepines. Risk factors for abuse include alcohol abuse, personality disorders in the patient or the patient's parent(s). Oxazepam undergoes phase II metabolism and, therefore, is less likely to be affected in patients with hepatic dysfunction.
Nursing: Physical Assessment/Monitoring
Assess other medications the patient may be taking for effectiveness and interactions. Assess for history of addiction; long-term use can result in dependence, abuse, or tolerance; periodically evaluate need for continued use. For inpatient use, institute safety measures and monitor effectiveness and adverse reactions. For outpatients, monitor therapeutic effectiveness and adverse reactions at beginning of therapy and periodically with long-term use. Can cause CNS depression (dose-related); monitor for sedation, dizziness, confusion, or ataxia which may impair physical and mental capabilities. Be alert to the possibility of suicide ideation. Taper dosage slowly when discontinuing. Assess knowledge/teach patient appropriate use, interventions to reduce side effects, and adverse symptoms to report.
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Capsule: 10 mg, 15 mg, 30 mg
Tablet: 15 mg [contains tartrazine]
Pricing: U.S. (www.drugstore.com)
Capsules (Oxazepam)
10 mg (30): $17.99
15 mg (30): $21.99
30 mg (30): $35.99
Capsules (Serax)
10 mg (30): $32.99
References
Hicks R, Dysken MW, Davis JM, et al, “The Pharmacokinetics of Psychotropic Medication in the Elderly: A Review,” J Clin Psychiatry, 1981, 42(10):374-85.
Mokhlesi B, Leikin JB, Murray P, et al, “Adult Toxicology in Critical Care: Part II: Specific Poisonings,” Chest, 2003, 123(3):897-922.
Moshkowitz M, Pines A, Finkelstein A, et al, “Skin Blisters as a Manifestation of Oxazepam Toxicity,” J Toxicol Clin Toxicol, 1990, 28(3):383-6.
Zileli MS, Teletar F, Deniz S, et al, “Oxazepam Intoxication Simulating Nonketo-Acidotic Diabetic Coma,” JAMA, 1971, 215(12):1986.
International Brand Names
Lexi-Comp.com
Last full review/revision August 2008
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