The only adverse event resulting in discontinuation of therapy in >3 % of patients treated with Cilostazol 50 or 100 mg twice a day, was headache, which occurred with an incidence of 1.3%, 3.5%, and 0.3% in patients treated with Cilostazol 50 mg twice a day, 100 mg twice a day, or placebo respectively. Other frequent causes of discontinuation included palpitation and diarrhea, both 1.1% for Cilostazol (all doses) versus 0.1% for placebo.