Effect of a combination of gemfibrozil and niacin on lipid levels.

To determine the effect of the combination of niacin and gemfibrozil on the lipid profile, a retrospective review was conducted of 161 patients who were prescribed a combination of gemfibrozil and niacin for 6 to 12 months at a community-based lipid clinic. Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol, total cholesterol, triglycerides, ratio of total cholesterol to HDL, alanine aminotransferase (ALT), and weight were measured at entry to the clinic, 2 months after dietary instruction, during single-agent therapy, and during combination therapy. Mean doses of niacin and gemfibrozil were 1,229 mg/day and 1,200 mg/day, respectively. Patient weight decreased significantly after dietary instruction and after institution of combination therapy. There were no significant changes in ALT levels with either single-agent therapy or with combination therapy. The combination of niacin and gemfibrozil produced marked and significant changes in lipid levels: total cholesterol and LDL decreased by 14%, HDL increased by 24%, the ratio of total cholesterol to HDL decreased by 30%, and triglycerides decreased by 52%. The combination of niacin and gemfibrozil in the setting of dietary instruction has a marked beneficial effect on serum lipid levels, and was most effective in patients with initial levels of HDL < 40 mg/dL, triglycerides > 250 mg/dL, and LDL > 160 mg/dL. No episodes of ALT elevation or symptomatic myositis were seen.