Zolpidem (Ambien)

1. General:

• Nonbenzodiazepine

  • Structurally unrelated to benzo’s, but acts in much the same manner

    • Binds to (subtype 1) GABA_A1 receptors

• Useful for the short-term treatment of insomnia

  • Primarily a sedative (rather than an anxiolytic)

2. Pharmacokinetics

• Rapidly absorbed in the GI tract following oral administration (75% reaches plasma)

• Only approx. 20% is metabolized in first-pass metabolism

  • Metabolized in the liver and excreted by the kidney’s

• Peak plasma levels reached in approx. 1 hour

2. Pharmacodynamics

• Produces sedation and promotes good sleep (w/o anxiolytic, anticonvulsant, or muscle-relaxant effects)

• Memory is affected

• Flumazenil reported to reverse memory impairments and overdoses

  • Flumazenil also reported to improve memory and learning, thus suggesting a possible role of endogenous benzo’s in memory function

2. Adverse Effects

• Drowsiness, dizziness, and nausea at therapeutic doses

  • Severe nausea and vomiting greatly limit overdoses

Category: Pharmacology Notes