Benzodiazepine Pharmacokinetics and Hypnotic Dosing

Generic name (trade name)	Time to peak plasma levels	Active substance half life	Dosing	Comments
Triazolam (Halcion)	0.75-2 hrs	2-6 hrs	0.125-0.25mg (0.125 mg elderly)	Useful for sleep onset. Higher doses are associated with greater memory impairment and rebound insomnia
Oxazepam (Serax)	2-4 hrs	5-20 hrs	15-30mg (10-20 mg elderly)	Rather slowly absorbed, best used to sustain sleep
Temazepam (Restoril)	1-2 hrs	5-20 hrs	15-30 mg	Useful for sleep onset, residual effects are uncommon
Alprazolam (Xanax)	1-2 hrs	6-20 hrs	0.25-1 mg	Higher risk of withdrawal symptoms
Bromazepam (Lectopam)	1-4 hrs	8-19 hrs	3-6 mg	Used primarily as anxiolytic
Lorazepam (Ativan)	1-4 hrs	10-20 hrs	0.5-2 mg	Intermediate onset and duration of hypnotic effect
Estazolam (Prosom)	1-2 hrs	10-24 hrs	1-2 mg (0.5-1 mg elderly)	Intermediate duration of hypnotic effect
Nitrazepam (Mogadon)	1-3 hrs	20-40 hrs	5-10 mg (2.5-5 mg elderly)	Accumulations with continuous use is common as are daytime effects
Clonazepam (Rivotril)	1-2 hrs	20-80 hrs	0.5-2 mg	Useful for sustaining sleep but accumulates with continuous use
Chlordiazepoxide (Librium)	1-4 hrs	<100 hrs	5-25 mg	Primarily anxiolytic use. Numerous long acting metabolites
Clorazepate (Tranxene)	0.5-1.5 hrs	<100 hrs	3.75-15 mg	Useful for insomnia where anxiety is a predominant feature as anxiolytic effects carry over to the next day
Diazepam (Valium)	0.5-1.5 hrs	<100 hrs	5-10 mg (2-5 mg elderly)	Rapid onset useful for sleep latency. Duration short due to rapid redistribution. Accumulation with regular use
Flurazepam (Dalmane)	0.5-1.5 hrs	<100 hrs	15-30 mg (15 mg elderly)	Rapid onset and prolonged duration, useful for sleep latency and early morning awakening. Accumulation with regular use
Ketazolam (Loftran)	2-3 hrs	<100 hrs	15-30 mg	Primarily used for anxiety. Residual effects with continuous use

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