Short term hypolipidemic effects of oral Lactobacillus sporogenes (360 million spores/day) were studied in 17 patients (mean age 45.6 years; males 15, females 2) with type II hyperlipidemia in an open label fixed dose trial. Over a period of 3 months, significant reductions were observed in total cholesterol (330 +/- 55 mg% to 226 +/- 46 mg%, p less than 0.001) and LDL-cholesterol (267 +/- 58 mg% to 173 +/- 54 mg%, p less than 0.001). The HDL-cholesterol was marginally increased (43.6 +/- 7 mg% to 46.8 +/- 8.9 mg%, p less than 0.05). There was no change in serum triglyceride concentration. Total cholesterol/HDL cholesterol and LDL cholesterol/HDL cholesterol ratios were significantly reduced after treatment (p less than 0.001). No adverse effect was noted. While the change in serum lipid levels on treatment was consistent with regard to total and LDL-cholesterol, it was not so in case of serum triglycerides and HDL-cholesterol. Oral Lactobacillus sporogenes therapy may prove to be an important hypolipidemic therapy after confirmation in larger trials.