Low-Dose Aspirin Therapy

Why take low-dose aspirin?

Aspirin, the common pain reliever that has been in our medicine cabinets for more than a century, also has a talent for prevention.

Aspirin prevents blood clots from forming in your arteries. This can prevent a heart attack or stroke.

Who should take low-dose aspirin?

For people who have had a heart attack: Aspirin can help prevent a second heart attack. Your doctor has probably already prescribed low-dose aspirin for you.

For people who have had a stroke: Aspirin can help prevent a second stroke or a Reference transient ischemic attack (TIA) Opens New Window, which is often a warning sign of an impending stroke.

For people who have never had a heart attack or stroke: Talk to your doctor before you start taking aspirin every day. Aspirin may reduce your chance of having a heart attack or a stroke if you have Reference coronary artery disease Opens New Window or certain risk factors, such as diabetes, high blood pressure, high cholesterol, or smoking. If you have a higher risk for a heart attack or stroke, aspirin will have even more benefit for you.

Aspirin may also be used by people who:

• Had Reference bypass surgery Opens New Window or Reference angioplasty Opens New Window.
• Had a Reference stroke Opens New Window or Reference transient ischemic attack Opens New Window (TIA).
• Have Reference peripheral arterial disease Opens New Window.
• Have Reference atrial fibrillation Opens New Window.

For help on the decision to take low-dose aspirin, see:

Opens New Window Aspirin: Should I Take Daily Aspirin to Prevent a Heart Attack or Stroke? Opens New Window

Doctors use different guidelines to decide who should take daily aspirin. But no matter which guideline your doctor follows, he or she will look at your health and at your risk for a heart attack or stroke. Then you and your doctor will balance the benefits and the risks of taking a daily aspirin to see if a daily aspirin is right for you.

If you have a relatively low risk for a heart attack or stroke, the benefits of preventive aspirin therapy may be outweighed by the increased risk of bleeding problems.

Your doctor can help you know your risk of having a heart attack or stroke and the risk of bleeding from aspirin. If you know your blood pressure and cholesterol numbers, you can use this Reference Interactive Tool: Are You at Risk for a Heart Attack? Reference to find out your risk.

Who should not take low-dose aspirin?

People who have certain health problems shouldn't take aspirin. These include people who:

• Have a stomach ulcer.
• Have recently had a stroke caused by bleeding in the brain.
• Are Reference allergic Opens New Window to aspirin.
• Have high blood pressure that isn't under control.
• Have Reference asthma Opens New Window that is made worse by aspirin.

If you think you are having a stroke, do not take aspirin because not all strokes are caused by clots. Aspirin could make some strokes worse.

Reference Gout Opens New Window can become worse or hard to treat for some people who take low-dose aspirin.

If you can't take aspirin, your doctor may have you take clopidogrel (Plavix) to help prevent a heart attack or a stroke.

If you take an anticoagulant, such as warfarin (Coumadin), talk with your doctor before taking aspirin, because taking both medicines can cause bleeding problems.

What precautions do I need to take?

Limit alcohol

Drinking 3 or more alcoholic drinks every day while taking daily aspirin increases your risk for liver damage and stomach bleeding. If your doctor recommends aspirin, limit or stop alcohol usage.

Talk to doctor before a surgery or procedure

Because aspirin reduces your blood's ability to clot, your doctor may want you to stop taking aspirin at least 5 days before any surgery, test, or dental procedure that may cause bleeding. Do not suddenly stop taking aspirin without talking to your doctor first. Talking to your cardiologist first is especially important if you have had a Reference stent Opens New Window placed in a Reference coronary artery Opens New Window.

Tell your doctor if you notice that you bruise easily or have other Reference signs of bleeding. These include bloody or black stools or prolonged bleeding from cuts or scrapes.

Tell your doctor about all your medicines

Aspirin should not be taken with many prescription and over-the-counter drugs, vitamins, herbal remedies, and supplements. So before you start aspirin therapy, talk to your doctor about all the drugs and other remedies you take.

Be careful taking pain relievers

Although Reference nonsteroidal anti-inflammatory drugs Opens New Window (NSAIDs), such as ibuprofen and naproxen, relieve pain and inflammation much like aspirin does, they do not affect blood clotting in the same way that aspirin does. Do not substitute NSAIDs for aspirin. NSAIDs may increase your risk for a heart attack or stroke.

If you need both aspirin and a pain reliever every day, talk to your doctor about what pain reliever you should take. If you take uncoated aspirin and ibuprofen at the same time, the aspirin may not work as well to prevent a heart attack. You may be able to use acetaminophen instead of ibuprofen to treat your pain. But if ibuprofen is your only option, avoid taking it during the 8 hours before and the 30 minutes after your aspirin dose. For example, you can take ibuprofen 30 minutes after your aspirin dose. If you take ibuprofen once in a while, it does not seem to cause problems.

Experts do not know if NSAIDs other than ibuprofen interfere with uncoated aspirin. Also, experts do not know if people who take a daily coated aspirin should be concerned about ibuprofen or other NSAIDs interacting with the aspirin. Talk to your doctor if you take these medicines every day.

More information

For more safety tips, see:

Reference Reference Blood Thinners Other Than Warfarin: Taking Them Safely

How do you take low-dose aspirin?

Your doctor will recommend a dose of aspirin and how often to take it. Most people take aspirin every day to help prevent a heart attack or a stroke, but others might take aspirin every other day.

Low-dose aspirin (81 mg) is the most common dose used to prevent a heart attack or a stroke. But the dose for daily aspirin can range from 81 mg to 325 mg. One low-dose aspirin contains 81 mg. One adult-strength aspirin contains about 325 mg.

For low-dose aspirin therapy, do not take medicines that combine aspirin with other ingredients such as caffeine and sodium.

Low-dose aspirin seems to be as effective in preventing heart attacks and strokes as higher doses.

Take aspirin with food if it bothers your stomach.

How does aspirin work to prevent a heart attack or stroke?

Aspirin protects you from having a clot-related stroke in the same way it protects you from having a heart attack.

Aspirin slows the blood's clotting action by reducing the clumping of platelets. Platelets are cells that clump together and help to form blood clots. Aspirin keeps platelets from clumping together, thus helping to prevent or reduce blood clots.

During a heart attack, blood clots form in an already-narrowed artery and block the flow of oxygen-rich blood to the heart muscle (or to part of the brain, in the case of stroke). When taken during a heart attack, aspirin slows clotting and decreases the size of the forming blood clot. Taken daily, aspirin's anti-clotting action helps prevent a first or second heart attack.

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This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.