Aspirin and Heart Disease

man holding a pill

Should you take aspirin to prevent heart attack?

AHA Recommendation

You should not take daily low-dose aspirin on your own without talking to your doctor. The risks and benefits vary for each person.

If you have had a heart attack or stroke, your doctor 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 patients with a history of heart attack or stroke. Always follow the treatment plans your health care provider has recommended for you.

Because of the risk of bleeding, aspirin therapy is not recommended if you have never had a heart attack or stroke, except for certain carefully selected patients. 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 doctor if any of these situations apply to you. You should not take daily low-dose aspirin without talking to a doctor 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 the age of 70

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 doctor 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 providers specifically recommend it as part of the 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 the blood's 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.
  • If a blood clot blocks a blood vessel that feeds the brain, it causes a stroke.

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

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

Should I take aspirin during a heart attack or stroke?

The more important thing to do if any heart attack warning signs occur is to call 911 immediately. Don't do anything before calling 911. In particular, don't take an aspirin, then wait for it to relieve your pain. Don't postpone calling 911. Aspirin won't treat your heart attack by itself.

After you call 911, the 911 operator may recommend that you take an aspirin. He or she can 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 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 provider. You should not start aspirin on your own.

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