Effects of long-term treatment with suloctidil on blood viscosity, erythrocyte deformability and total fibrinogen plasma levels in diabetic patients.

1-(4-Isopropylthiophenyl)-2-n-octylaminopropanol (suloctidil, Sulocton), a drug introduced into clinical practice for the treatment of cerebral and peripheral vascular insufficiency and its complications, has been shown to decrease blood hyperviscosity after long-term treatment in diabetic patients. Suloctidil was particularly effective in lowering measured blood viscosity at high shear rate (230 s-1). At low shear rate (0.77 s-1) a decreasing effect was also observed but reached a statistically significant level only after one month. Since neither total plasma fibrinogen levels nor red blood cell deformability were modified by suloctidil treatment, its lowering effect on blood hyperviscosity could be due to a hitherto unrecognized mechansim of action.