Dipyridamole is used to prevent thromboembolism in patients who have received prosthetic heart valves and to assess heart health in patients who cannot tolerate a standard stress test. The drug is a vasodilator and stimulates blood flow to the heart. When used in place of a stress test, the results mimic the effects of exercise. The drug is available as a tablet or as an IV solution. It may not be appropriate for people who suffer from asthma, angina or an irregular heartbeat. It may also adversely affect people who have muscle weakness. As with all drugs, before taking this medication, you should make your doctor aware of any medications you may be taking, including prescription and over-the-counter drugs, as well as supplements and herbal remedies. You should also let your doctor know if you are pregnant or breastfeeding, and if you have any allergies to drugs or foods.