Clinical Overview
Quazepam is a long-acting benzodiazepine indicated for insomnia. It has one of the longest half-lives among benzodiazepines (39-73 hours), making it effective for sleep maintenance but also increasing the risk of next-day sedation and accumulation with repeated dosing. It is less commonly prescribed due to these pharmacokinetic properties.
Primary Clinical Applications
Quazepam is indicated for the treatment of insomnia, particularly for patients with sleep maintenance difficulties who need sustained sleep throughout the night. Its long duration of action can provide consistent sleep without middle-of-the-night awakening, but this also increases the risk of hangover effects.
Mechanism and Clinical Profile
Quazepam enhances GABA activity at benzodiazepine receptors, providing sedative and hypnotic effects. Its very long half-life (39-73 hours) and active metabolites result in prolonged therapeutic effects but also increase the risk of drug accumulation and next-day impairment with repeated use.
Clinical Considerations
The extended half-life makes quazepam suitable for patients with severe sleep maintenance insomnia but problematic for those who need to be alert the next day. The risk of accumulation and tolerance makes it less suitable for long-term use compared to shorter-acting alternatives. It should be used with particular caution in elderly patients due to increased fall risk and cognitive impairment.
Prescribing Information
Dosing & Administration
Insomnia – Adults:
- Initial: 15 mg at bedtime
- Range: 7.5-15 mg at bedtime
- Maximum: 15 mg at bedtime
Elderly:
- Initial: 7.5 mg at bedtime
- Maximum: 7.5 mg at bedtime
- Use with extreme caution due to long half-life
Administration:
- Take immediately before bedtime
- Ensure 8+ hours available for sleep due to long half-life
- Limit treatment duration to 7-10 days when possible
- Avoid alcohol and other CNS depressants
Indications
- Treatment of insomnia
- Particularly for sleep maintenance difficulties
Contraindications
- Hypersensitivity to benzodiazepines
- Sleep apnea syndrome
- Severe respiratory insufficiency
- Severe hepatic insufficiency
- Myasthenia gravis
- Pregnancy (particularly first trimester)
Warnings & Precautions
- Boxed Warning: Risk of abuse, misuse, dependence; respiratory depression with opioids
- Very long half-life: High risk of next-day impairment and accumulation
- Complex sleep behaviors: Sleep-driving, sleep-eating reported
- Physical dependence: Risk increases with dose and duration
- Withdrawal syndrome: May be prolonged due to long half-life
- Falls risk: Particularly high in elderly due to prolonged effects
- Cognitive impairment: May persist into next day
Drug Interactions
- Opioids: Increased risk of respiratory depression and death
- CNS depressants: Enhanced sedation and respiratory depression
- Alcohol: Dangerous potentiation of effects
- CYP3A4 inhibitors: May increase quazepam levels
Adverse Reactions
Common (>5%):
- Drowsiness, headache, fatigue, dizziness
- Dry mouth, dyspepsia
Next-day effects:
- Prolonged sedation, impaired driving ability
- Memory impairment, ataxia
Serious:
- Respiratory depression, complex sleep behaviors
- Severe withdrawal syndrome
Special Populations
- Elderly: Maximum 7.5 mg due to increased sensitivity and fall risk
- Hepatic Impairment: Contraindicated in severe impairment
- Pregnancy: Category X – avoid in pregnancy
- Long half-life considerations: High risk of accumulation and next-day impairment
Medical Disclaimer: This information is for educational purposes only and is not intended as medical advice. Always consult with qualified healthcare professionals before making any treatment decisions. Individual patient circumstances may vary significantly.
