title: Naltrexone blockade of nicotine effects in cigarette smokers.
abstract: BACKGROUND
  The role of endogenous opiate systems in cigarette smoking remains unclear. In laboratory animals, opiate antagonists block many of the effects of nicotine, but in humans they do not consistently alter smoking behavior.
  
  
  OBJECTIVE
  This study explored the effects of naltrexone, alone and in combination with nicotine, on smoking behavior.
  
  
  METHODS
  In a double-blind, double-dummy, within-subjects design, 19 regular smokers received four treatments of 1 week duration: naltrexone tablet (50 mg) plus placebo skin patch, placebo tablet plus nicotine skin patch (21 mg/24 h), naltrexone tablet plus nicotine skin patch, and placebo tablet plus placebo skin patch. During each treatment, subjects rated their responses to nicotine-containing and denicotinized cigarettes in the laboratory, and to their own brand of cigarette smoked ad libitum outside the laboratory.
  
  
  RESULTS
  Pretreatment with the nicotine patch attenuated smoking-induced decreases in craving, negative affect, and rates of ad lib smoking, and potentiated the aversiveness of a cigarette. Naltrexone reversed these effects of the nicotine patch, and produced negative effects on mood.
  
  
  CONCLUSIONS
  The blockade of nicotine's effects by naltrexone supports a role for opioid mechanisms in cigarette smoking.
authors.affiliation: Department of Psychiatry, Duke University Medical Center, Durham, NC 27710, USA. lbrauer@acpub.duke.edu
authors.forename: L H
authors.initials: LH
authors.lastname: Brauer
authors.forename: F M
authors.initials: FM
authors.lastname: Behm
authors.forename: E C
authors.initials: EC
authors.lastname: Westman
authors.forename: P
authors.initials: P
authors.lastname: Patel
authors.forename: J E
authors.initials: JE
authors.lastname: Rose
mesh_terms: D000328:Adult; D000339:Affect / Q000187:drug effects; D000704:Analysis of Variance; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009271:Naltrexone / Q000494:pharmacology*; D009292:Narcotic Antagonists / Q000494:pharmacology*; D009538:Nicotine / Q000037:antagonists & inhibitors*; D010919:Placebos; D012907:Smoking / Q000097:blood / Q000503:physiopathology* / Q000523:psychology*; D013375:Substance Withdrawal Syndrome / Q000209:etiology / Q000517:prevention & control; D011795:Surveys and Questionnaires
chemical_list: D009292:Narcotic Antagonists; D010919:Placebos; D009271:Naltrexone; D009538:Nicotine