Aspirin Dipyridamole: What It Is, How It Works, and What You Need to Know

When you hear aspirin dipyridamole, a fixed-dose combination medication used to prevent blood clots after a stroke or transient ischemic attack (TIA). Also known as Aggrenox, it combines two well-known drugs: low-dose aspirin and extended-release dipyridamole. This combo doesn’t just add two effects—it creates a stronger, more targeted defense against clotting in brain arteries. Unlike taking aspirin alone, this pairing works on two different pathways that lead to platelets sticking together. Aspirin blocks the enzyme that makes thromboxane, a substance that makes platelets clump. Dipyridamole boosts adenosine levels, which naturally slows platelet activation. Together, they reduce the chance of another stroke more effectively than either drug alone.

People who’ve had a TIA, a temporary blockage of blood flow to the brain, often called a mini-stroke are the main group this medication targets. Studies, including the European Stroke Prevention Study, showed that patients on aspirin dipyridamole had fewer repeat strokes than those on aspirin by itself. It’s not for everyone—people with severe asthma, ulcers, or bleeding disorders should avoid it. And while it’s not a first-line choice for heart attack prevention, it’s one of the few options specifically approved for secondary stroke prevention in the U.S. and Europe.

Many patients wonder how it compares to other antiplatelet therapy, medications that stop platelets from forming dangerous clots like clopidogrel or ticagrelor. Those drugs are often used after stents or heart attacks, but aspirin dipyridamole holds its ground for stroke patients, especially when cost and long-term use matter. It’s cheaper than newer agents and has been around long enough that doctors know how to manage side effects like headaches, which are common at first but usually fade.

What you won’t find in most drug guides is how often this combo is overlooked. Some patients get prescribed aspirin alone, even when guidelines say the combo is better for stroke prevention. Others get switched to clopidogrel because it’s newer, but studies don’t show it’s superior for this specific use. The real question isn’t which drug is trendier—it’s which one fits your history, risk, and tolerance.

Below, you’ll find detailed comparisons and real-world advice on how aspirin dipyridamole stacks up against other treatments, what to expect when you start it, how to handle side effects, and when it might not be the right choice for you. These aren’t generic summaries—they’re practical guides written for people who’ve been through a stroke or know someone who has. You’ll see what works, what doesn’t, and what most doctors don’t take the time to explain.