Effects of ticlopidine on blood fibrinogen and blood viscosity in peripheral atherosclerotic disease

Ten patients with peripheral atherosclerotic disease (PAD) treated with 750 mg/d of 5-(2-chlorophenylmethyl)-4,5,6,7-tetrahydrothieno(3,5-c-pyridine) hydrochloride (ticlopidine, Tiklid®) were studied for three months. As controls, a similar group of patients treated with a traditional vasodilator (nicotinate) was studied. The aim of our study was to evaluate the effect of ticlopidine both on the clinical evolution of the disease and on rheologic, coagulative and platelet parameters. A progressive increase of maximal walking distance was noted during the three months of therapy with ticlopidine and limited to the first 30 days of treatment with nicotinate. The fibrinogen levels were significantly lowered during 90 days of treatment with ticlopidine, while that was not evident in the nicotinate group. There was also a slight improvement of blood viscosity in the ticlopidine group (not evident in the nicotinate group), but it was not statistically significant. No further modifications of investigated data were found in the two groups of patients. The clinical benefit of ticlopidine in PAD without adverse reactions can be confirmed at least at the dosage of 750 mg/d instead of the usual dose of 500 mg/d. A direct or indirect action of ticlopidine on plasma fibrinogen is suggested. This observation may supply new clues for the understanding of the mechanism of action of this drug.