Evidence exists that alcohol abuse frequently coexists with narcotic addiction and methadone maintenance treatment, and it is the major factor in the development of cirrhosis and liver failure. This study of patients hospitalized for alcohol detoxification compares the quantity of alcohol consumed by alcohol abusers, addicted to narcotics or in a methadone maintenance treatment program, to that consumed by patients not involved with narcotic addiction. Mean daily alcohol consumption was not significantly different in either group using narcotics, including methadone, or in the subgroup of methadone maintenance patients, from the amount consumed by nonnarcotic abusers. Determination of temporal sequence in the use of these substances revealed that in 68% regular alcohol abuse preceded narcotic use. Alcohol abuse reportedly began after entering a methadone maintenance treatment program in 29% of our patients. Alcohol abusers who were in a methadone maintenance treatment program were significantly younger than those who did not use narcotics, including methadone. Time interval according to the patients' estimates, from onset of regular alcohol consumption to heavy drinking, was not significantly different in the two groups.