Drug Guide
Zaleplon
Classification
Therapeutic: Sedative/Hypnotic for Insomnia
Pharmacological: GABA-A Receptor Agonist, Non-benzodiazepine
FDA Approved Indications
- Short-term treatment of insomnia, primarily for sleep onset difficulties
Mechanism of Action
Zaleplon binds selectively to GABA-A receptor complexes containing the alpha-1 subunit, enhancing GABA-mediated chloride ion influx, leading to sedative effects and facilitating sleep onset.
Dosage and Administration
Adult: 10 mg taken immediately before bedtime; may be adjusted to 5 mg or 20 mg based on response and tolerability.
Pediatric: Not indicated for pediatric use.
Geriatric: Initially 5 mg due to increased sensitivity; dose adjustment may be necessary.
Renal Impairment: Use with caution; consider dose reduction.
Hepatic Impairment: Use with caution; typically start with 5 mg.
Pharmacokinetics
Absorption: Rapidly absorbed, peak plasma levels in approximately 1 hour.
Distribution: Widely distributed; volume of distribution approx. 0.5-0.8 L/kg.
Metabolism: Extensively metabolized in the liver primarily via aldehyde oxidase and CYP3A4.
Excretion: Metabolites excreted mainly in urine; parent compound minimally excreted.
Half Life: Approximately 1 hour, supporting its rapid onset and short duration of action.
Contraindications
- Hypersensitivity to zaleplon or any component
Precautions
- History of drug abuse or dependency, hepatic impairment, depression, or suicidal ideation.
- Use caution in patients with a history of complex sleep behaviors such as sleepwalking or sleep-driving.
Adverse Reactions - Common
- Headache (Common)
- Dizziness (Common)
- Nausea (Common)
- Somnolence (Common)
Adverse Reactions - Serious
- Complex sleep behaviors (e.g., sleepwalking, sleep-driving) (Rare)
- Angioedema, hypersensitivity reactions (Rare)
- Respiratory depression (Rare)
Drug-Drug Interactions
- CNS depressants (additive sedative effects)
- OATP inhibitors (may increase zaleplon levels)
Drug-Food Interactions
N/ADrug-Herb Interactions
N/ANursing Implications
Assessment: Monitor for signs of excessive sedation, sleep behaviors, or adverse reactions.
Diagnoses:
- Risk for injury due to impaired cognition or sleep behaviors.
- Risk for overdose.
Implementation: Administer immediately before bedtime. Avoid alcohol and other CNS depressants. Monitor hepatic function in long-term use.
Evaluation: Assess sleep quality, side effects, and adverse reactions.
Patient/Family Teaching
- Take drug exactly as prescribed, immediately before bed.
- Avoid alcohol and CNS depressants.
- Report any sleep behaviors such as sleepwalking.
- Avoid driving or operating machinery until alertness is confirmed.
Special Considerations
Black Box Warnings:
- Complex sleep behaviors (e.g., sleepwalking, sleep-driving, sleep-eating) may occur and have led to injuries.
- Use with caution in the elderly due to increased risk of falls.
Genetic Factors: Variability in CYP3A4 activity may affect drug levels.
Lab Test Interference: None known.
Overdose Management
Signs/Symptoms: Excessive sedation, respiratory depression, coma.
Treatment: Supportive care, airway management, possible use of flumazenil in specific cases (off-label), monitor vital signs, and provide respiratory support as needed.
Storage and Handling
Storage: Store at room temperature away from light and moisture.
Stability: Stable for shelf life as indicated on packaging.