During the study, scientists discovered that the drug reduced the risk of a stroke by a quarter and the risk of dangerous side-effects by a half in patients, reports the Telegraph.
The findings are particularly important as millions of people take a low dose of aspirin daily, as it is known to reduce the risk of having a heart attack or stroke in people, especially if they have already had one.
Taking cilostazol, a drug which prevents clotting and is used to treat muscle cramps, instead would not only be more powerful but also reduce the risk of haemorrhage - one of the major dangers of taking aspirin.
Authors Dr Deepak Bhatt and Dr Dharam Kumbhani of Harvard Medical School, said the trial suggested that cilostazol offered "prevention beyond the protection provided by aspirin".
In the study, 2757 patients who had already suffered a stroke were split into two roughly equal groups - one of which was given aspirin and the other cilostazol for as long as five years.
During the trial, it was found that 2.76 per cent of the cilostazol group suffered a stroke compared to 3.71 per cent of the aspirin group - a 26 per cent reduction.
Severe bleeding occurred in half as many patients taking cilostazol - 0·77 per cent per year - compared to patients taking aspirin - 1·78 per cent per year.
However, non-serious side-effects including headache, diarrhoea, palpitation, and dizziness, were significantly more common in the cilostazol group.
The authors of the study said that more trials were needed to see that the effect was universal as the trial was carried out in Japan.
The study has been published in the Lancet.