Dipyridamole: Uses, Dosing, Side Effects, and Practical Tips

Dipyridamole is a medicine that helps prevent blood clots and can widen blood vessels. Doctors commonly use it in two ways: combined with low-dose aspirin to lower the risk of repeat ischemic stroke, and alone as a vasodilator during certain heart stress tests. It’s a prescription drug, often known by the brand Aggrenox when paired with aspirin, or as generic dipyridamole for other uses.

How it works is fairly straightforward. Dipyridamole reduces platelet stickiness and raises levels of substances that relax vessel walls. That helps keep clots from forming and improves blood flow. It doesn’t dissolve clots already there; it lowers the chance new ones will form.

Typical dosing depends on the use. For stroke prevention, the well-known combo pill contains 200 mg extended-release dipyridamole plus 25 mg aspirin taken twice daily. For cardiac stress tests, short-acting dipyridamole is given by IV in controlled medical settings. Never change doses without talking to your doctor.

Expect a few common side effects. Headache is the most frequent complaint — it may feel like a pressure or tightness and often gets better after a few days. Other side effects include dizziness, nausea, stomach upset, flushing, and sometimes bleeding. Because it affects clotting, watch for signs of unusual bruising, blood in urine or stool, or long nosebleeds. If any of those happen, contact your healthcare provider right away.

Interactions matter. Combining dipyridamole with other blood thinners or antiplatelet drugs raises bleeding risk. Tell your doctor if you take warfarin, direct oral anticoagulants, clopidogrel, or even high doses of NSAIDs like ibuprofen. Certain antidepressants and herbal supplements like ginkgo might also change bleeding risk. Your prescriber will weigh risks and benefits.

Who should avoid dipyridamole? People with active bleeding, severe low blood pressure, or certain heart conditions may not be good candidates. Pregnant or breastfeeding people should discuss safety with their doctor — data are limited. Older adults may be more sensitive to dizziness and falls, so monitoring is important.

Practical tips for everyday use: take extended-release capsules as prescribed, usually twice a day, and swallow them whole. Try to take doses at the same times each day and with food if stomach upset occurs. Keep a list of all medicines and share it with every provider. If you’re scheduled for surgery or dental work, tell the team you take dipyridamole so they can manage bleeding risk.

If you have questions about cost or whether generic or brand options are right for you, your pharmacist can help. And if a medicine causes severe side effects or you’re worried about interactions, don’t guess — call your doctor. Dipyridamole can be very helpful, but like any medicine, it works best when used carefully.

Store dipyridamole at room temperature away from moisture and heat. Keep it out of reach of children. You’ll need a prescription and follow-up visits so your doctor can check blood pressure and watch for bleeding. If you miss a dose, take it soon unless the next dose is close — don’t double up if unsure.