DrugindexOnline^{2nd edition}

Pronouncation: (ZAL-eh-plahn)
Class: Sedative and hypnotic

Trade Names:
Sonata
- Capsules 5 mg
- Capsules 10 mg

Sotacor (Canada)

Mechanism of Action

Pharmacology

Interacts with the gamma-aminobutyric acid receptor complex.

Pharmacokinetics

Absorption

Rapid absorption. T _max is about 1 hr. Absolute bioavailability is about 30% because it undergoes significant presystemic metabolism. High fat meals prolonged the absorption, delaying T _max about 2 hr and reducing C _max about 35%.

Distribution

Vd is about 1.4 L/kg. Protein binding is about 60%.

Metabolism

Extensively metabolized with about 1% of dose excreted unchanged in the urine. Primarily metabolized by aldehyde oxidase to form 5-oxo-zaleplon. Metabolized to a lesser extent by cytochrome P450 3A4. Metabolites converted to glucoronides and eliminated in the urine.

Elimination

T _½ is about 1 hr. It is rapidly eliminated. Oral dose plasma Cl is about 3 L/hr/kg. IV dose plasma Cl is about 1 L/hr/kg. 70% of dose recovered in urine within 48 hr.

Special Populations

Renal Function Impairment

No dose adjustment in mild to moderate renal insufficiency. It has not been studied in severe renal insufficiency.

Hepatic Function Impairment

Primarily metabolized by the liver and undergoes presystemic metabolism. Oral Cl was reduced 70% and 87% in compensated and decompensated patients, respectively. Reduce dose in mild to moderate hepatic impairment. Do not use in severe hepatic insufficiency.

Race

C _max and AUC were increased 37% and 64%, respectively in Asian populations.

Indications and Usage

Short-term treatment of insomnia.

Contraindications

Standard considerations.

Dosage and Administration

Adults

PO 5 to 20 mg at bedtime.

Elderly/Debilitated Patients

PO 5 to 10 mg at bedtime.

Hepatic Impairment (Mild to Moderate)

PO 5 mg at bedtime.

Storage/Stability

Store at room temperature in tightly closed, light-resistant container out of the reach of children.

Drug Interactions

Alcohol, other CNS depressants

Additive or potentiation of CNS depressant effects.

Cimetidine

May elevate zaleplon plasma levels, increasing the therapeutic and adverse effects.

Rifampin

May reduce zaleplon plasma levels, reducing the effectiveness.

Laboratory Test Interactions

None well documented.

Adverse Reactions

Cardiovascular

Migraine.

CNS

Depression; hypertonia; nervousness; abnormal thinking; headache; anxiety; amnesia; dizziness; depersonalization; hallucinations; hypesthesia; paresthesia; somnolence; tremor; vertigo.

Dermatologic

Pruritus; rash; photosensitivity.

EENT

Conjunctivitis; abnormal vision; ear pain; eye pain; hyperacusis; parosmia.

GI

Constipation; dry mouth; anorexia; colitis; dyspepsia; nausea.

Genitourinary

Dysmenorrhea.

Respiratory

Bronchitis; epistaxis.

Miscellaneous

Back pain; chest pain; arthritis; abdominal pain; asthenia; fever; malaise; peripheral edema.

Precautions

Pregnancy

Category C .

Lactation

Excreted in breast milk.

Children

Safety and efficacy not established.

Elderly

Impaired motor or cognitive function with repeated exposure or unusual sensitivity is a concern.

Hepatic Function

Use with caution and in reduced dosage.

Amnesia

May occur.

Depression

Administer with caution to depressed patients or those with suicidal tendencies. Signs and symptoms of depression may be intensified.

Withdrawal

Rebound insomnia on the first night following withdrawal occurs in some patients.

Overdosage

Symptoms

Drowsiness, mental confusion, lethargy, ataxia, hypotonia, hypotension, respiratory depression, coma, death.

Patient Information

• Instruct patient to take the medication exactly as directed. Do not increase or decrease the dose or use longer than as directed by health care provider.
• Instruct patient to take zaleplon immediately before going to bed or after going to bed if patient has difficulty falling asleep. Avoid taking medication after a high-fat or heavy meal.
• Instruct patient not to take zaleplon if able to get at least 4 hours of sleep before active again and only for a short period of time (1 or 2 days and generally less than 1 or 2 weeks) to avoid the problems of prolonged use.
• Discuss with primary caregiver and patient the benefits and risks of prolonged use including: memory problems, tolerance, dependence, changes in behavior and thinking, and withdrawal symptoms.
• Instruct patient to inform primary caregiver if taking or planning to take any OTC or prescription medications.
• Warn patient of the dangers of drinking alcohol and taking zaleplon or any other sleeping pill or CNS depressant.
• Caution patient that zaleplon may have some residual sedation at first and to not drive an automobile, operate dangerous machinery, or engage in activities that require mental alertness and coordination until knowing how the patient will react to this drug.
• Instruct patient to inform health care provider if experiencing any unusual or disturbing thoughts or if signs of depression occur.
• Inform patient of potential sleeping problems the first few nights after stopping the medication.
• Caution patient to inform the health care provider if pregnant, planning to become pregnant, or breast-feeding.