II. Class
- Long acting Benzodiazepine
III. Indications
- Anxiety Disorder
- Partial Seizures (adjunct)
- Alcohol Withdrawal
IV. Dosing: Adults
-
Anxiety Disorder
- Start 3.75 mg to 15 mg orally twice daily (or 7.5 mg to 15 mg orally once at bedtime)
- Typical dose: 15 mg orally twice daily
- Maximum Total Daily Dose: 60 mg in divided doses (15 mg maximum dose in elderly)
-
Alcohol Withdrawal
- Day 1: 30 mg orally once, then give additional 30 to 60 mg/day divided in 3 to 4 doses
- Day 2: 45 to 90 mg/day divided in 3 to 4 doses
- Day 3: 22.5 to 45 mg/day divided in 3 to 4 doses
- Day 4: 15 to 30 mg/day divided in 3 to 4 doses
- Gradually taper and discontinue once patient stable on 7.5 mg once daily
- Maximum total daily dose: 90 mg/day divided
-
Partial Seizures (adjunct, age >13 years)
- Start 7.5 mg orally 2 to 3 times daily
- May increase by no more than 7.5 mg/dose each week as needed
- Maximum total daily dose: 90 mg/day divided
V. Dosing: Children
-
Partial Seizures (adjunct, age 9 to 12 years old)
- Start 7.5 mg orally twice daily
- May increase by no more than 7.5 mg/dose each week as needed
- Maximum total daily dose: 60 mg/day divided
VI. Pharmacokinetics
- Half Life: 40 to 50 hours (up to 100 hours)
VII. Metabolism
- Chlorazepate is decarboxylated first in the Gastrointestinal Tract to the active agent desmethyldiazepam, and then absorbed
- Desmethyldiazepam is then metabolized to Oxazepam via CYP3A4 and CYP2C19
VIII. Safety
- Pregnancy Category X (esp. first trimester)
- Avoid in Lactation
- Schedule IV Controlled Substance
IX. Resources
- Chlorazepate (DailyMed)
X. References
- (2019) Med Lett Drugs Ther 61(1578): 121-6
- (2020) Presc Lett, Resource #361206, Appropriate Use of Benzodiazepines
- Olson (2020) Clinical Pharmacology, Medmaster Miami, p. 55
- Hamilton (2020) Tarascon Pocket Pharmacopoeia