title: Open-label pilot study of quetiapine treatment for cannabis dependence.
abstract: BACKGROUND
  There are no efficacious pharmacotherapies for cannabis dependence. The effects of quetiapine are well matched to the symptoms of cannabis withdrawal and could be useful in the treatment of cannabis dependence.
  
  
  OBJECTIVE
  To evaluate quetiapine for the treatment of cannabis dependence and determine the optimal dosing.
  
  
  METHODS
  In an eight-week open-label outpatient pilot trial, we evaluated the feasibility of quetiapine treatment for cannabis dependence in 15 outpatients. Quetiapine was gradually titrated to 600 mg or the maximum tolerated dose.
  
  
  RESULTS
  The mean study retention was 6.5 weeks (±2.3), with 67% of participants completing all eight weeks of the trial. The mean maximum dose achieved was 197 mg/day (range: 25-600 mg/day). Only two of the 15 participants were able to achieve the target dose of 600 mg daily. There were no serious adverse events and no participants were discontinued from the trial due to adverse effects. The most common reported adverse effects were fatigue (80% of participants) and somnolence (47%). From baseline to week 8, the modeled overall decrease in daily dollar value of marijuana was 76.3% (CI: 63.4%, 84.7%). Over the eight weeks of the study, there was a 46.9% (CI: 11%, 68.3%) decrease in urine tetrahydrocannabinol-9-carboxylic acid (THCOOH) levels.
  
  
  CONCLUSIONS
  These preliminary results are promising in that quetiapine treatment was tolerated by cannabis-dependent patients and associated with decreased cannabis use. The recommended maximum target dose for cannabis-dependent patients is 300 mg daily. These preliminary data support further evaluation of quetiapine as a treatment for cannabis dependence.
authors: New York State Psychiatric Institute, Division of Substance Abuse , New York .
authors: John J
authors: JJ
authors: Mariani
authors: Martina
authors: M
authors: Pavlicova
authors: Agnieszka K
authors: AK
authors: Mamczur
authors: Adam
authors: A
authors: Bisaga
authors: Edward V
authors: EV
authors: Nunes
authors: Frances R
authors: FR
authors: Levin
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D003987:Dibenzothiazepines / Q000008:administration & dosage / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000188:drug therapy*; D010865:Pilot Projects; D000069348:Quetiapine Fumarate; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D014150:Antipsychotic Agents; D003987:Dibenzothiazepines; D000069348:Quetiapine Fumarate
keywords: Cannabis; dependence; pharmacotherapy; quetiapine; treatment