Lipid disorders are common among patients with HIV and tend to worsen with potent antiretroviral therapy. Lipid-lowering drugs are not always effective, and few data address interactions between antiretroviral drugs and lipid-lowering agents. Additional agents for the treatment of lipid metabolism disorders in HIV-infected patients are needed. Niacin, which is highly effective for similar lipid disorders in the general population, may be effective in treating lipid disorders in patients with HIV.