This study examines the effect of alcohol withdrawal on lipoprotein(a) [Lp(a)] in 24 male, middle-aged chronic alcohol abusers admitted for withdrawal therapy. Serum concentration of Lp(a) was determined before and during the first 3 weeks of abstinence. The changes in three sialylated proteins [Lp(a), alpha 1-antitrypsin (alpha 1-AT), and haptoglobin (Hp)] and in desialylated transferrin (CDT) were also determined in 14 patients. After the 3 weeks of withdrawal therapy, the mean and median Lp(a) concentrations increased (p = 0.0001). The changes in Lp(a) levels were not related to the changes in dietary intake nor to the decrease in total HDL, HDL3, HDL2 cholesterol, Apo A-I, and Apo B. In the subgroup of 14 chronic alcohol abusers, Lp(a) levels increased parallel with Hp and alpha 1-AT, whereas CDT decreased. It is concluded that the impact of alcohol on sialylated proteins may be one of the mechanisms responsible for the increase in plasma Lp(a) after alcohol withdrawal.