Aspirin and Heart Disease

Should you take aspirin to prevent heart attack?

AHA Recommendation

You should not take daily low-dose aspirin without talking to your primary health care professional. The risks and benefits vary for each person.

If you have had a heart attack or stroke, your health care professional may want you to take a daily low dose of aspirin to help prevent another. Aspirin is part of a well-established treatment plan for people with a history of heart attack or stroke.

Because of the risk of bleeding, aspirin therapy is not recommended if you have never had a heart attack or stroke, except for certain select people. Your health care professional will consider your overall health and risk factors for heart attack before recommending aspirin therapy.

If you’re over 70, taking aspirin to prevent a first heart attack or stroke could do more harm than good.

Know the risks.

Because aspirin thins the blood, it can cause several complications. Tell your health care team if any of these situations apply to you. You should not take daily low-dose aspirin without talking to your health care professional if you:

  • Have an aspirin allergy or intolerance
  • Are at risk for gastrointestinal bleeding or hemorrhagic stroke
  • Drink alcohol regularly
  • Are undergoing any simple medical or dental procedures
  • Are over 70 years old

There is a risk of stomach problems, including stomach bleeding, for people who take aspirin regularly. Alcohol use can increase these stomach risks. If you are told to take aspirin, ask your health care professional if it is safe for you to drink alcohol in moderation.

People with diabetes who do not have a history of heart attack or stroke may not need to take aspirin therapy, unless their health care team specifically recommends it as part of their overall treatment plan.

How does aspirin help prevent heart attack and stroke?

Most heart attacks and strokes occur when the blood supply to a part of your heart muscle or brain is blocked. This usually starts with atherosclerosis, a process in which deposits of fatty substances, cholesterol, cellular waste products, calcium and other substances build up in the inner lining of an artery. This buildup is called plaque.

Plaque usually affects large and medium-sized arteries. Plaques can grow large enough to significantly reduce blood flow through an artery. But most of the damage occurs when a plaque becomes fragile and ruptures. Plaques that rupture cause blood clots to form that can block blood flow or break off and travel to another part of the body. This is called an embolism.

  • If a blood clot blocks a blood vessel that feeds the heart, it causes a heart attack.
  • A stroke occurs when a blood clot blocks a blood vessel that feeds the brain.

Aspirin thins the blood, which helps prevent blood clots from forming.

Certain people will be prescribed aspirin combined with another antiplatelet drug (such as clopidogrel, prasugrel or ticagrelor). This is also known as dual antiplatelet therapy (DAPT). Learn more about DAPT.

Should I take aspirin during a heart attack or stroke?

The most important thing to do if heart attack warning signs occur is to call 911 immediately. Don't do anything before calling 911. Don't take an aspirin, then wait for it to relieve your pain. Don't postpone calling 911.

After you call 911, the 911 operator may recommend that you take an aspirin. They will make sure that you don't have an allergy to aspirin or a condition that makes using it too risky. If the 911 operator doesn't talk to you about taking an aspirin, the emergency medical technicians or the physician in the hospital Emergency Department will give you an aspirin if it's right for you.

Taking aspirin isn't advised during a stroke, because not all strokes are caused by blood clots. Most strokes are caused by clots, but some are caused by ruptured blood vessels. Taking aspirin could potentially make these bleeding strokes more severe.

What’s the bottom line?

The best way to know if you can benefit from aspirin therapy is to ask your health care professional. You should not start aspirin therapy on your own.


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