Available agents affect platelets by distinctly different mechanisms, and, hence, their clinical effects are not identical. Both ticlopidine and its congener clopidogrel have been shown to be more effective than aspirin in large randomized trials, but the differences were small. Combination of ticlopidine or clopidogrel with aspirin offers theoretical advantages in augmenting the antiplatelet effect. These combinations have been shown to be more effective than aspirin in short-term treatment following coronary stent placement, but the relative efficacy and safety during prolonged use to prevent stroke are being assessed in ongoing clinical trials. Other antiplatelet agents of uncertain value for cerebrovascular disease include pentoxiphylline and indobufen .
Most authorities recommend aspirin as the initial antiplatelet therapy to prevent stroke.
It is unclear whether aspirin doses between 50mg - 1300mg offer more or less benefit. Albers et al. Guidelines for the Management of TIA's.