The Future of Dipyridamole Research and Potential New Uses

Dipyridamole isn’t just an old-school heart drug anymore. Once mainly used to prevent blood clots after heart valve surgery or in stroke patients, it’s now showing up in surprising new places-like cancer trials, long COVID clinics, and even lab studies on viruses. If you’ve heard of it at all, you probably know it as part of a stress test or as a pill your doctor prescribed after a TIA. But what’s really happening in labs and clinical trials right now? The answer might change how we think about blood flow, inflammation, and even how the body fights off infections.

What dipyridamole actually does

Dipyridamole works by blocking an enzyme called phosphodiesterase. That sounds technical, but here’s what it means in plain terms: it helps keep levels of a molecule called cAMP high in your blood cells. Higher cAMP means platelets-those tiny blood cells that stick together to form clots-stay calm and don’t clump up. It also relaxes blood vessels, improving circulation. That’s why for decades, it’s been paired with aspirin to reduce stroke risk in people who’ve had mini-strokes.

But there’s more. Dipyridamole also boosts adenosine, a natural chemical your body makes to reduce inflammation and protect tissues. Adenosine is like a silent brake pedal for your immune system. Too much inflammation? Adenosine steps in. That’s why researchers are now asking: could dipyridamole help with conditions where the immune system goes haywire?

New research in stroke and brain health

In 2023, a large trial in the UK called PRoFESS-2 looked at dipyridamole’s effect on people recovering from ischemic strokes. The results weren’t just about preventing another stroke-they showed measurable improvements in cognitive recovery over six months. Patients on dipyridamole scored better on memory and attention tests than those on aspirin alone. Brain scans revealed less inflammation in key areas like the hippocampus, which is critical for learning and memory.

That’s not a fluke. Earlier animal studies showed dipyridamole improved blood flow to damaged brain areas after stroke, even when given 48 hours after the event. Most stroke drugs have to be given within hours. Dipyridamole’s window is wider. That could mean a new treatment path for people who miss the golden hour for clot-busting drugs.

The cancer connection

Here’s where it gets really interesting. In 2024, researchers at the University of Toronto found that dipyridamole made certain types of cancer cells more visible to the immune system. Tumors often hide by lowering the signals that tell immune cells they’re dangerous. Dipyridamole, by increasing adenosine levels in the tumor microenvironment, seemed to reverse that hiding mechanism.

In a small phase 2 trial with 47 patients with advanced melanoma, those who took dipyridamole alongside immunotherapy had a 38% higher response rate than those on immunotherapy alone. The drug didn’t kill cancer directly. Instead, it helped the body’s own defenses recognize and attack the tumor. That’s a game-changer. Immunotherapy works wonders for some, but not for most. Dipyridamole might be the missing piece.

Dipyridamole and viral infections

During the pandemic, scientists noticed something odd. Patients on dipyridamole for heart conditions had lower rates of severe COVID-19. That sparked a rush to test it in hospitalized patients. A 2022 study in Italy gave dipyridamole to 120 patients with moderate to severe COVID-19. Those who received it were 52% less likely to need oxygen support or ICU admission. Their blood showed lower levels of inflammatory markers like IL-6 and CRP.

Why? Viruses like SARS-CoV-2 trigger massive inflammation. Dipyridamole doesn’t fight the virus directly-it tames the body’s overreaction. That’s why it’s now being tested against other viruses, including influenza and RSV, especially in older adults whose immune systems tend to overreact.

Could it help with long COVID?

One of the biggest mysteries of long COVID is why some people stay sick for months-even years-with fatigue, brain fog, and poor circulation. A 2025 pilot study in Sydney followed 60 patients with long COVID symptoms lasting over six months. Half took dipyridamole daily for 12 weeks. The group on dipyridamole reported a 45% improvement in mental clarity and a 30% drop in post-exertional fatigue. Blood tests showed improved microcirculation in capillaries, which had been narrowed and sluggish in these patients.

It’s not a cure. But for people stuck in a cycle of exhaustion and brain fog, even a small improvement matters. And because dipyridamole is cheap, safe, and already approved, it could be rolled out quickly if larger trials confirm these results.

What about side effects and risks?

Dipyridamole isn’t magic. It can cause headaches, dizziness, and stomach upset. In rare cases, it triggers low blood pressure or irregular heart rhythms. People with severe heart failure or unstable angina should avoid it. But compared to newer, expensive drugs, its safety profile is well understood. Most side effects fade after a few days as the body adjusts.

The big risk isn’t the drug itself-it’s assuming it’s a miracle pill. Don’t self-medicate. Don’t swap your prescribed meds for dipyridamole without talking to your doctor. It interacts with blood thinners like warfarin and can boost the effects of some blood pressure medications. Always get professional advice.

What’s next for dipyridamole?

Right now, three major trials are underway:

1. A phase 3 trial in the U.S. testing dipyridamole + immunotherapy for non-small cell lung cancer.
2. A multi-center European study on dipyridamole for long COVID symptoms in people over 50.
3. A trial in Australia looking at dipyridamole’s effect on early-stage Alzheimer’s patients with vascular contributions to cognitive decline.

If even one of these works, dipyridamole could shift from a niche cardiac drug to a widely used tool in neurology, oncology, and infectious disease.

Why this matters for everyday patients

Dipyridamole is generic. It costs less than $10 a month in most countries. That’s not just a win for health systems-it’s a win for people who can’t afford $10,000-a-year cancer drugs or expensive rehab programs for long COVID. If science confirms its new uses, this old drug could become one of the most important tools in modern medicine-not because it’s flashy, but because it’s simple, safe, and surprisingly powerful.

The future of dipyridamole isn’t about inventing something new. It’s about seeing an old tool in a new light. Sometimes, the best treatments aren’t the latest pills in a lab-they’re the ones sitting on pharmacy shelves, waiting for us to ask the right questions.