Brand name
- DORAL®
Drug Class
Benzodiazepines
Preparations
- Tablets: 7.5 mg and 15 mg
Indications
- Insomnia (Difficulty Sleeping)
Pharmacology
Pharmacodynamics:
Exact mechanism is not known >>> 1,4-benzodiazepine class presumably exerts their effects by binding to stereo-specific receptors at several sites within the central nervous system (CNS).
Metabolism
Pharmacokinetics:
- Absorption: Gastrointestinal tract
- Distribution: Peak plasma concentration of quazepam is approximately 20 ng/mL after a 15 mg dose after about 2 hours. Plasma protein binding: >95%
- Metabolism: Metabolized in liver. Half-life of about 30 minutes. Two major metabolites: 2-oxoquazepam and N-desalkyl-2-oxoquazepam.
- Excretion: Urine + Feces
Dosing
1. Insomnia: (Adults)
- Initial dose:5 mg orally at bedtime
- Maintenance dose: May increase to 15 mg orally at bedtime (Reduce the dose after 2 consecutive nights)
(Use the lowest effective dose, as adverse effects are dose related)
2. Insomnia: (Geriatrics)
- Start at the lowest dose possible (Which is clinically effective)
3. Renal Dysfunction
No dose adjustment recommended.
(Monitor the patient closely for any signs of overdose like sedation)
4. Liver Dose Adjustments
No dose adjustment recommended.
(Monitor the patient closely for any signs of overdose like sedation)
5. Dialysis
- Hemodialysis: No dose adjustment recommended.
- Peritoneal dialysis: No available data
Drug Interactions
- Psychoactive drugs (Opioids, Benzodiazepines, Anti- Psychotics and etc.)
- Alcohol (Ethanol)
- Quazepam Increases the plasma concentrations of drugs that are substrates of CYP2B6 (e.g., efavirenz and bupropion) may result if co administered with Quazepam (Enzyme inhibitor effect) >>> Quazepam does not inhibit CYP2C8 and CYP2E1
- Anticonvulsants
- Antihistamines
Adverse Effects
More Frequent:
- Drowsiness
- Headache
Less frequent:
- Dizziness
- Dry mouth (Xerostomia)
- Dyspepsia
Contraindications
- Known hypersensitivity to Quazepam or Benzodizepines.
- Patients with established or suspected sleep apnea, or with pulmonary insufficiency.
- Sodium-Oxybate
Pregnancy and Breastfeeding
Pregnancy: Category X
Lactation: NOT recommended in nursing mother
Precautions
1. The failure of insomnia to remit after 7 to 10 days of treatment may indicate the presence of a primary psychiatric and/or medical illness that should be evaluated.
2. Avoid using dangerous machinery vehicles while taking Quazepam! Due to its sedative hypnotic effect.
3. Avoid driving while taking Quazepam! Due to its seeative hypnotic effect.
4. Caution in concomitant use with CNS-depressant medications! May cause synergistic effect >>> may increase sedation.
5. Caution in concomitant use with Alcohol! >>> Increases sedative effects.
6. Watch for possible Complex Behaviors: preparing and eating food, making phone calls, or having sex. (Patients usually do not remember these events)
7. Caution for Severe anaphylactic and anaphylactic reactions
8. Abuse: Caution in administering Quazepam to individuals known to be addiction prone or those whose history suggests they may increase the dosage on their own initiative.
9. Dependence: The use of benzodiazepines may lead to dependence as defined by the presence of a withdrawal syndrome on discontinuation of the drug.
10. Tolerance: As defined by a need to increase the dose in order to achieve the same therapeutic effect seldom occurs in-patients receiving recommended doses under medical supervision >>> Caution for Tolerance to sedation may occur with benzodiazepines especially in those with drug seeking behaviour.
11. Caution in Patients with major depressive disorder: Risk that the signs and symptoms of depression may be intensified. Appropriate precautions (e.g, limiting the total prescription size and increased monitoring for suicidal ideation) should be considered.
12. Educate, Counsel the patient, caregivers, family for the associated benefit and risks.
13. If benzodiazepines are taken on a prolonged and regular basis (even for periods as brief as 6 weeks), patients should be advised not to stop taking them >>> do a gradual tapering to discontinuation:
- Withdrawal symptoms: convulsions, tremor, abdominal and muscle cramps, vomiting, and sweating, dysphoria and insomnia.
14. Pediatric Use: Safety and effectiveness in children below the age of 18 years have not been established.
15. Geriatric Use: Dose selection for an elderly patient should be cautious (Start with lower doses due to higher chances of hepatic and renal diseases).
16. Paradoxical reactions such as acute rage, stimulation or excitement may occur; should such reactions occur, Quazepam should be discontinued >>> Rebound phenomena.
17. Over dosage:
Symptoms:
- Sedation, somnolence, confusion, impaired, coordination, diminished reflexes, untoward effects on vital signs, coma and possible cardiorespiratory arrest.
Treatment:
- Continuous monitoring of vital signs including EKG immediately.
- Immediate attention should be given to the maintenance of an adequate airway and support of ventilation.
- Cardiopulmonary resuscitation may be required
- Flumazenil (Benzodiazepine antagonist –Specific antidote) >>> 0.2 mg IV in 13-30 minutes >>> If no response after 30 minutes, add 0.3 mg in 30 seconds one minute later. Maximum total dose: 3 mg/hr (contact your regional Poison Control Centre for more information)
Section
This document is prepared by the “Mental Health for All” team. This document is provided for information purposes only and does not necessarily represent endorsement by or an official position of the Essentials of Medicine. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient’s medical history.