Background: In humans, 6-beta-naltrexol is the major metabolite of naltrexo
ne, and its effectiveness at suppressing alcohol consumption in any species
has not been previously investigated. Naltrexone is an opiate antagonist t
hat reduces excessive drinking in many species, including humans with alcoh
ol dependence. Whether 6-beta-naltrexol is an active metabolite that contri
butes to the efficacy of naltrexone remains unknown.
Methods: Placebo and four doses of 6-beta-naltrexol were given by intraperi
toneal injection to outbred Wistar rats and alcohol consumption was measure
d using a limited access model.
Results: 6-beta-Naltrexol reduced alcohol consumption in a dose-dependent m
anner. At doses 7.5, 12.5, and 25 mg/kg, 6-beta-naltrexol significantly dec
reased consumption of a 6% ethanol solution compared with saline control gr
oups.
Conclusions: These data suggest that there may be a potential clinical use
for 6-beta-naltrexol in recovering alcoholics.