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Should you take aspirin to prevent a heart attack or stroke?

A pile of aspirin.

Are you considering taking aspirin to protect your heart and blood vessels? For safety’s sake, check with your doctor first. Aspirin’s benefits may or may not be worth its risks.

If you have a headache, toothache or other everyday pain, aspirin can be a good, occasional friend. If you've had a heart attack or a common type of stroke, aspirin may become a trusted companion—maybe even a lifesaver.

That's because aspirin can do more than ease minor aches and pains. Taken correctly, it may also protect the heart and blood vessels.

How aspirin works

Aspirin is an antiplatelet drug, meaning it works on platelets, cells in the blood that clump together to help form blood clots.

The body needs clots to repair cuts. But clots can cause problems.

In diseased arteries narrowed with fatty deposits of plaque, clots can block the circulation of blood. If a clot blocks blood flow to the heart, it causes a heart attack. If a clot blocks blood flow to the brain, it causes a stroke.

Aspirin helps keep blood flowing through your body by limiting the ability of platelets to clump, according to the American College of Cardiology.

But in doing so, aspirin can also make bleeding more likely.

In some people, aspirin can potentially cause serious bleeding in the stomach or the brain. You're more likely to have bleeding when you take aspirin if, for instance, you already have stomach problems, such as ulcers, or you're older than 70.

Who aspirin can help

Your doctor may recommend taking aspirin every day if you've had a heart attack or a clot-caused stroke, according to the American Heart Association (AHA). Research shows that aspirin helps prevent these cardiovascular events from occurring again.

In addition, daily aspirin may be recommended after you've had a procedure, such as coronary bypass surgery or angioplasty, to place a stent in your coronary arteries.

In these situations, the benefits of taking aspirin outweigh the small chance of bleeding.

But most people should not take aspirin daily to prevent a first heart attack, stroke or other blood vessel problems. The reason? Research has found that in people at low to moderate risk of heart disease, the risks of internal bleeding and other side effects outweigh aspirin's benefits.

Still, some experts say aspirin may help people at high risk avoid their first heart attack or stroke if they have a low risk for bleeding. This may include people with a strong family history of heart disease or those with plaque buildup in their arteries, according to the AHA.

Only a doctor can tell you if aspirin's benefits outweigh its risks in your case.

That's why it's important to talk to your doctor before taking aspirin every day. If you regularly take aspirin without your doctor's OK, you could harm your health.

The right dose

If your doctor does recommend that you take aspirin, be sure to ask how much to use. When aspirin is taken to prevent blood vessel problems, the dosage is usually 81 milligrams a day. This is called low-dose aspirin. (By comparison, regular pills for occasional pain relief contain 325 milligrams of aspirin.)

Here are a few other ways to help reduce unwanted side effects:

  • Take aspirin with food to avoid an upset stomach.
  • Tell your doctor if you drink alcohol. Taking aspirin with alcohol can increase your risk of bleeding.
  • Tell your doctor about any other medicines and supplements you're taking. Some of them may cause problems when taken with aspirin. One example is other blood thinners, such as warfarin, notes the U.S. Food and Drug Administration (FDA).

Don't go it alone: Consult your doctor

Despite its potential risks, aspirin is a key treatment for many people, especially those hoping to prevent a second heart attack or stroke.

Just check with your doctor before using it, FDA urges.

More tips to avoid a second heart attack

If you've survived one heart attack, it's important to know what you can do to avoid another. Learn about some of the healthy choices you may need to make.

Reviewed 2/26/2021

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