About Dipyridamole Antiplatelet Agent(Platelet Aggregation Inhibitor), Vasodilator. Mechanism of Action of Dipyridamole The drug exerts it`s antithrombotic action by interfering with platelet aggregation. It inhibits phosphodiesterase, blocks uptake and degradation of adenosine (local mediator involved in auto regulation of coronary blood flow in response to ischaemia.), Potentiate prostacyclin (PG I2) and increase cyclic AMP in platelets and interferes with aggregation. Indications for Dipyridamole 1. Thromboembolic disorders 2. Angina pectoris 3. Inhibition of platelet adhesion in patients with prosthetic heart valves Interactions for Dipyridamole Oral anti-coagulants & anti-arrhythmic agent Adenosine: Efficacy enhanced by dipyridamole. Antacids: Reduces efficacy of dipyridamole. Aminophylline: Reverses vasodilatation effect of dipyridamole. Aspirin: Useful combination for prevention of thromboembolic phenomenon.