Naltrexone is a narcotic antagonist that has been shown to reduce alcohol craving and alcohol use in patients with alcohol dependence. It should not be used as exclusive treatment but only as an adjunct to a comprehensive program that includes psychologic and social treatment approaches such as those in Alcoholics Anonymous or professional programs. The two most serious complications of naltrexone therapy are the precipitation of narcotic withdrawal in patients taking narcotics, and hepatotoxicity. The latter complication occurs only at dosages much higher than the 50 mg per day recommended for treatment of alcohol dependence. Alcohol is known to enhance opioid receptors. Evidently, naltrexone blockade of these receptors results in reduced craving for alcohol, less of a "high" while drinking and less alcohol use.