Drug Interactions between dipyridamole and sildenafil

Caffeine may interfere with the effects of dipyridamole in dilating the arteries. You should avoid caffeine-containing products for at least 24 hours before an imaging procedure involving dipyridamole given by injection. However, no special precaution is necessary if you are taking dipyridamole orally for maintenance.

If you are receiving therapy with sildenafil you should avoid the regular consumption of large amounts of grapefruits and grapefruit juice. Grapefruit can raise the levels of sildenafil in your body and delay the time it takes for the medication to work. Do not increase or decrease the amount of grapefruit products in your diet without first talking to your doctor.

Ask your doctor before using dipyridamole together with caffeine. Using these medications together can decrease the effects of dipyridamole. It is recommended that caffeine including caffeine be avoided for 12 to 24 hours before dipyridamole administration. You may need a dose adjustment or special test if you use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.