Hyperlipidemia and increased serum lipoprotein (Lp)(a) are independent risk factors for atherosclerosis and its complications. Serum Lp(a) concentration is not influenced by most lipid-lowering therapies other than niacin. Recently aspirin also has been reported to decrease its levels. In the current study, we evaluated the serum levels of Lp(a) and lipids in 25 patients with first-ever diagnosed ischemic stroke, aged 21 to 60 years, and compared their levels with an equal number of age- and sex-matched healthy control subjects. In addition, the effect of aspirin on Lp(a) levels was studied by estimating its levels after 4 weeks of daily treatment with 150 mg of aspirin. Both groups were comparable regarding their anthropometric measurements and routine laboratory parameters except that erythrocyte sedimentation rate was higher in the patients. Serum lipids were not significantly different between the two groups, although Lp(a) levels were significantly higher in the patients (27.40 +/- 22.30 mg/dL) as compared with the control subjects (14.68 +/- 11.75 mg/dL) (P = .005). Twenty of 25 patients (80%) had serum Lp(a) levels of more than 10 mg/dL, whereas only 11 of 25 control subjects (44%) had serum Lp(a) levels of more than 10 mg/dL (P = .009). After 4 weeks of treatment with aspirin, Lp(a) levels declined significantly (46.24%) from baseline 27.40 +/- 22.30 mg/dL to 14.73 +/- 10.47 mg/dL (P < .001). Patients with baseline levels greater than 25 mg/dL showed greater decline (55.63%) compared with those with levels less than 25 mg/dL (26.63%) (P = .008). Results of our study confirm that aspirin lowers the increased Lp(a) levels in patients with ischemic stroke.