The authors studied the effects of oral loading with 5-HTP on REM fragmentation in a group of alcoholics who were abstinent following acute ethanol withdrawal. Decreased fragmentation was found in the majority of subjects, and those subjects with low baseline REM efficiency (i.e., greater fragmentation) showed more improvement from the drug than did subjects who were less impaired initially. The authors suggest that there is an organic decrement of serotonin during ethanol withdrawal which is partially reversed by 5-HTP loading.