Numerous prior studies of serum lipid levels during anabolic steroid (AS) use have uniformly demonstrated dramatic adverse lipid profiles (eg, average high-density lipoprotein [HDL] depression of 50%) during administration of 17 alpha-alkylated AS. In contrast, the existing studies of 17 beta-esterified AS have shown mild or absent lipid effects (eg, HDL depression 0% to 16%) with these agents. Thus, the potential effects on serum lipids of individual AS are an important clinical consideration. The present study was therefore designed to investigate the lipid effects of nandrolone, a 17 beta-esterified AS. Twenty-one men and three women had lipid profiles measured before and after administration of nandrolone decanoate 100 mg intramuscularly (IM) once a week for 6 weeks. No significant change was noted in HDL cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol, triglycerides, the total cholesterol to HDL-C ratio, or the LDL-C/HDL-C ratio from nandrolone treatment. Moreover, observed trends toward HDL-C depression (-2.00 +/- 8.83 mg/dL; values reported are for men only unless noted otherwise) and LDL elevation (+5.05 +/- 20.45 mg/dL) were small. In power analysis, HDL-C depressions of 6.3, 7.6, or 8.7 mg/dL during nandrolone were ruled out with powers of 80%, 95%, and 99%, respectively.