Chronic alcoholism is related to brain damage (i.e., volume changes) in both men and women. There is an open question whether the brains of women are more vulnerable than those of men to alcohol toxicity. The present follow-up study focuses on a direct comparison of sex-related differences in alcoholic brain shrinkage and its reversibility. In a prospective design, a random sample of 65 alcoholics of both sexes (51 males and 14 females) was studied. Computerized tomography brain scans before and after a 6-week inpatient treatment program with controlled abstinence revealed a significant re-expansion of the brain as assessed by linear measurements. By controlling for moderating variables such as age, mean daily alcohol consumption, liver dysfunction, etc. the degree of brain shrinkage was found to be similar in men and women despite significantly shorter ethanol expositions in the women. These findings corroborate the hypotheses of other investigators about basic biological differences between the two sexes as to the effects of alcohol. The hypothesis of an enhanced vulnerability of women to acute and chronic complications of alcoholism is supported.