title: Combining naltrexone and prazosin in a single oral medication decreases alcohol drinking more effectively than does either drug alone.
abstract: BACKGROUND
  Naltrexone (NTX) is underutilized in clinical treatment settings because its efficacy is modest, and it is not effective for all alcoholics and, when it is effective, a significant number of alcoholics fail to maintain initial treatment gains and subsequently relapse to heavy drinking. This has slowed acceptance of NTX by the treatment community, and there is a clear need for additional treatments for alcoholism and alcohol use disorders. Given that NTX and prazosin can each reduce alcohol drinking in rats selectively bred for alcohol preference and high voluntary alcohol drinking (alcohol-preferring "P" rats), we tested whether a combination of NTX + prazosin is more effective in decreasing alcohol drinking than is either drug alone.
  
  
  METHODS
  P rats were given access to a 15% (v/v) alcohol solution for 2 hours daily. Rats were fed NTX and prazosin, alone or in combination, prior to onset of the daily 2-hour alcohol access period for 4 weeks and the effect of drug treatment on alcohol and water intake was assessed.
  
  
  RESULTS
  During the first week of treatment, neither a low dose of NTX, nor prazosin, was effective in decreasing alcohol intake when each drug was administered alone, but combining the 2 drugs in a single medication significantly reduced alcohol intake. The combination was as effective as was a higher dose of NTX. Using a low dose of NTX in combination with prazosin may reduce the potential for undesirable side effects early in treatment which, in turn, may improve patient compliance and result in a more successful outcome when NTX is used for treating alcoholism and alcohol use disorders.
  
  
  CONCLUSIONS
  Combining low-dose NTX and prazosin in a single medication may be more useful than is either drug alone for treating both inpatient and outpatient alcoholics and heavy drinkers early in the treatment process.
authors.affiliation: Indiana University School of Medicine , Indianapolis, Indiana.
authors.forename: Janice C
authors.initials: JC
authors.lastname: Froehlich
authors.forename: Brett J
authors.initials: BJ
authors.lastname: Hausauer
authors.forename: Dennis D
authors.initials: DD
authors.lastname: Rasmussen
mesh_terms: D000284:Administration, Oral; D058668:Adrenergic alpha-1 Receptor Antagonists / Q000008:administration & dosage; D000428:Alcohol Drinking / Q000188:drug therapy* / Q000523:psychology; D000437:Alcoholism / Q000188:drug therapy* / Q000523:psychology; D000818:Animals; D004338:Drug Combinations; D004357:Drug Synergism; D008297:Male; D009271:Naltrexone / Q000008:administration & dosage*; D009292:Narcotic Antagonists / Q000008:administration & dosage; D011224:Prazosin / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D004338:Drug Combinations; D009292:Narcotic Antagonists; D009271:Naltrexone; D011224:Prazosin
keywords: Alcoholism Treatment; Genetic Selection; Naltrexone; Prazosin