Effect of the serotonin blocker sarpogrelate on circulating interleukin-18 levels in patients with diabetes and arteriosclerosis obliterans.

We aimed to evaluate the effect of treatment with sarpogrelate, a serotonin 2A receptor antagonist, on circulating interleukin (IL)-18 levels in patients with diabetes and arteriosclerosis obliterans. Patients received sarpogrelate (100 mg 3 times daily) for 2 months. We evaluated the degree of cryaesthesia (a feeling of cold in the foot and toes) as the clinical outcome, and measured circulating IL-18, IL-6 and lipid protein concentrations. An improvement in clinical outcome occurred after initiation of sarpogrelate therapy; a significant decrease in IL-18 levels was observed after 2 months of therapy. Levels of IL-6 and lipid proteins, including triglyceride, total cholesterol and high-density lipoprotein cholesterol, were not significantly altered by treatment. Our data suggest that by reducing circulating IL-18 levels, sarpogrelate treatment may contribute to the inhibition of arteriosclerosis obliterans progression in patients with diabetes.