The protein moiety of lipoprotein (a) [Lp(a)] has a high degree of homology to plasminogen. The effect of oxandrolone, an anabolic steroid agent, on plasma plasminogen and Lp(a) was determined. Subjects (n=14) received oxandrolone (20 mg/d) for 14 days. Blood was obtained on days 0, 1, 3, 7, 9, and 14; after discontinuation of oxandrolone, blood was obtained on days 21, 28 and 42. Samples were analyzed for plasma plasminogen and Lp(a). After 7 days of administration of oxandrolone, the plasma plasminogen level increased [100±21 to 174±21%, (p<0.0001)]. Serum Lp(a) was decreased by day 3 [22.9±33.6 to 12.5±19.1 mg/dl, (p<0.01)]  and continued to decrease over the 14 days of drug treatment [22.9±33.6 to 6.0±6.5 mg/dl, (p<0.0002)]. After discontinuation of oxandrolone, serum Lp(a) remained significantly depressed on day 21 compared to baseline. Reduction of elevated serum Lp(a) levels with oxandrolone may be considered for those at increased risk for cardiovascular disease.