title: Induction of the metabolism of etizolam by carbamazepine in humans.
abstract: OBJECTIVE
  To examine the effect of carbamazepine on the single oral dose pharmacokinetics of etizolam.
  
  
  METHODS
  Eleven healthy male volunteers received carbamazepine 200 mg/day or placebo for 6 days in a double-blind, randomized, crossover manner, and on the sixth day they received a single oral 1-mg dose of etizolam. Blood samplings and evaluation of psychomotor function by the Digit Symbol Substitution Test and Stanford Sleepiness Scale were conducted up to 24 h after etizolam dosing. Plasma concentration of etizolam was measured using high-performance liquid chromatography.
  
  
  RESULTS
  Carbamazepine treatment significantly decreased the peak plasma concentration (17.5+/-4.1 ng/ml versus 13.9+/-4.1 ng/ml; P<0.05), total area under the plasma concentration-time curve (194.8+/-88.9 ng h/ml versus 105.9+/-33.0 ng h/ml; P<0.001), and elimination half-life (11.1+/-4.6 h versus 6.8+/-2.8 h; P<0.01) of etizolam. No significant change was induced by carbamazepine in the two pharmacodynamic parameters.
  
  
  CONCLUSIONS
  The present study suggests that carbamazepine induces the metabolism of etizolam.
authors.affiliation: Department of Psychiatry, Yamagata University School of Medicine, Yamagata, 990-9585, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Kondo
authors.forename: T
authors.initials: T
authors.lastname: Fukasawa
authors.forename: N
authors.initials: N
authors.lastname: Yasui-Furukori
authors.forename: T
authors.initials: T
authors.lastname: Aoshima
authors.forename: A
authors.initials: A
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Inoue
authors.forename: T
authors.initials: T
authors.lastname: Tateishi
authors.forename: K
authors.initials: K
authors.lastname: Otani
mesh_terms: D000284:Administration, Oral; D000328:Adult; D018712:Analgesics, Non-Narcotic / Q000494:pharmacology; D019540:Area Under Curve; D002220:Carbamazepine / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D018592:Cross-Over Studies; D003975:Diazepam / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004347:Drug Interactions; D006207:Half-Life; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate / Q000187:drug effects; D014149:Tranquilizing Agents / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics
chemical_list: D018712:Analgesics, Non-Narcotic; D014149:Tranquilizing Agents; D002220:Carbamazepine; C044610:etizolam; D003975:Diazepam