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Medication (name): Aspirin

Commonly Used Brand and Generic Names:

Generic name: Acetylsalicylic acid (ASA)

Common brand names: Bayer, Bufferin

General category: Blood thinner, nonsteroidal anti-inflammatory drug, salicylate

]]> Current Uses


  • Pain relief
  • Fever reduction
  • Headache]]> relief
  • Heart disease
  • ]]>Arthritis]]> (swelling, stiffness, joint pain)

]]> What the Research Shows

Benefits for those with known coronary artery disease include:

  • For those who have not yet had a heart attack, regular use of aspirin can reduce overall risk of heart attack or stroke by 25%.
  • For those who have just had a heart attack, starting 162 milligrams a day of aspirin (half a standard-sized tablet) within 24 hours of the first heart attack cuts the risk of dying by more than 20%.

Benefits for those not diagnosed with coronary artery disease include:

  • Doses of 75-160 mg per day are as effective as higher doses. Consider 75-160 mg aspirin per day for people at higher risk (especially those with a 10-year CHD risk of 10% or greater)
  • In men over 50, there is reasonable evidence that taking a regular-strength aspirin (350 milligrams) every other day or taking 81 milligrams of aspirin every day reduces the chance of developing coronary artery disease.

According to the US Preventive Services Task Force, the following people are at increased risk for heart disease and should consider preventive aspirin therapy in consultation with their physician:

]]> Mechanism for How It Works

  • Analgesic/Anti-inflammatory, nonsteroidal —This inhibits the body’s production of a hormone-like substance, prostaglandin, which is a chemical that causes pain by stimulating muscles contractions and blood vessel dilation. Aspirin may also fight inflammation in a plaque caused by atherosclerosis]]> .
  • Antithrombotic (blood thinning)/Platelet aggregation inhibitor —This prevents platelets from releasing the prostaglandin thromboxane, which causes platelets to clump together in a blood clot. This helps prevent potentially fatal formation of new blood clots in diseased blood vessels.

]]> Side Effects

Drug Interactions

  • Anticoagulants (blood thinners): Coumadin (warfarin), heparin, Plavix (clopidogrel), Ticlid (ticlopidine), or Trental (pentoxifylline)—The blood can be too thinned and cause bleeding.
  • Antidiabetics, oral (diabetes medicine you take by mouth)—Salicylates may increase the effects of the antidiabetic medicine; a change in dose may be needed if a salicylate is taken regularly.
  • Inflammation or pain medicine , except narcotics
  • Probenecid (eg, Benemid)—Salicylates can keep probenecid from working properly for treating gout.
  • Sulfinpyrazone (eg, Anturane)—Salicylates can keep sulfinpyrazone from working properly for treating gout; also, taking a salicylate, especially aspirin, with sulfinpyrazone may increase the chance of bleeding.
  • Tetracyclines (medicine for infection), taken by mouth—Buffered aspirin may keep these medicines from working properly if taken too close to them.
  • Urinary alkalizers—These medicines may make the salicylate less effective by causing it to be removed from the body more quickly.
  • Vancomycin (eg, Vancocin)—The chance of serious side effects may be increased.
  • Valproic acid (eg, Depakene)—Taking these medicines together with a salicylate, especially aspirin, may increase the chance of bleeding.

Nutrient/Supplement Interactions

Do not take the following with aspirin except on medical advice. These medications or supplements can increase the blood-thinning properties of aspirin, other anticoagulants, and other natural products.

The following can decrease the effects of blood-thinning drugs, like aspirin:

These herbs can increase the risk of stomach problems when combined with aspirin and other anti-inflammatory drugs:

Aspirin and other nonsteroidal anti-inflammatory drugs can decrease the effects of, or cause a deficiency of the following:


Other Potential Concerns

Low-dose aspirin increases risk for gastrointestinal bleeding and hemorrhagic stroke]]> . Do not use without medical advice if you are at increased risk for these diseases.

  • Do not take aspirin if you have any of the following conditions:
    • Liver or kidney disease
    • ]]>Peptic ulcer]]> or other gastrointestinal bleeding disorder, or those at risk for these disorders
    • Allergy or intolerance to aspirin or other nonsteroidal anti-inflammatory drugs
    • ]]>Hemophilia]]> or other bleeding problems—the chance of bleeding may be increased
    • ]]>Gout]]> —salicylates can make this condition worse and can also lessen the effects of some medicines used to treat gout
    • ]]>Asthma]]>
  • Persons under the age of 21 should not take aspirin because of the potential of developing ]]>Reye’s syndrome]]> , a rare but serious disorder caused by abnormal responses to aspirin given during a viral illness. Acetaminophen should be given instead.
  • Pregnant women should not take aspirin during the last 3 months of pregnancy unless ordered by a doctor because it may increase the length of pregnancy, prolong labor, cause other problems during delivery, or cause severe bleeding in the mother before, during, or after delivery.


What to Watch For (Physical/Biochemical/Physiological)

  • Stomach irritation
  • Increased bleeding time
  • Dizziness/ vertigo]]>
  • Nausea/vomiting
  • Ringing or buzzing in the ears, hearing loss
  • Severe or continuing headaches


The American Heart Association recommends aspirin for patients who have experienced a myocardial infarction (heart attack), unstable angina, ischemic (blood clot-caused) stroke, or transient ischemic attacks (TIAs or "little strokes") if not contraindicated. This recommendation is based on sound evidence from clinical trials that shows that aspirin helps prevent the recurrence of events such as heart attack, stroke, or unstable angina.

Take only the amount of aspirin ordered by your doctor. If you need a medicine to relieve pain, a fever, or arthritis, your doctor may not want you to take extra aspirin. It is a good idea to discuss this with your doctor, so that you will know ahead of time what medicine to take.

Do not stop taking this medicine for any reason without first checking with the doctor who directed you to take it.