Studies on ethanol-exposed animals have revealed changes in anionic phospholipids in brain membranes. The intention of this study was to investigate whether there was a similar effect on man. Assuming platelets to be an adequate model for CNS synaptosomes, concentration and fatty acid composition of anionic phospholipids, phosphatidylserine (PS) and phosphatidylositol (PI) in the platelet membrane from alcoholics after a debauche period were examined and compared to controls. Ethanol effects on neutral lipids were also analysed in order to obtain a comprehensive view. No quantitative difference was found in anionic phospholipids between alcoholics and controls. Fatty acid composition of individual phospholipids revealed significant changes which were more obvious in neutral phospholipids than in anionic. Oleic acid was increased and linoleic and arachidonic acids were decreased. After 1 week of detoxification, the abnormalities did not decrease, on the contrary they increased and total phospholipid concentration per platelet was significantly higher than in controls. It is concluded that the ethanol toxicity on bone marrow hampers the use of platelets as a model for synaptosomes but that the observed lipid abnormalities might play a major role in the impairment of platelet function in alcoholics.