The control of alcohol intake is complex. Because of the carbohydrate characteristics of beverage alcohol and the ability of carbohydrates to boost levels of brain serotonin, it has been thought for years that the specific neurotransmitter may have a role in alcohol-seeking behavior. This contention has been supported by a variety of animal studies. One study on humans reported on 16 heavy drinking men (consuming an average of six drinks per day) who were treated for 2-week periods with 200 mg per day of zimelidine, followed by 2-week periods of placebo. The subjects, evaluated as outpatients, were asked to record their alcohol intake patterns. While on zimelidine, there was a significant decrease in the number of drinks per day as well as the number of days on which drinking occurred. In a second study, healthy men aged 20 to 42 who were relatively light drinkers (one to three times per week) were given 200 to 300 mg of zimelidine on a single occasion. Two hours after taking the drug orally they were given alcohol and their reaction evaluated. The investigators report a significant decrease (as much as 20 percent) in feelings of euphoria for the 12 subjects compared to their response without zimelidine pretreatment. In spite of these findings, however, the author warns that the potential dangers of using antidepressants among alcoholics, especially if they are mixed with alcohol, might be too high in relationship to the relatively modest improvement likely to be seen with their clinical use.