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                           (This sheet is summary of links to the above website as of July 2004)


What is aspirin?

Aspirin is a drug which can help fight heart disease and stroke, along with its long-known benefits of relieving pain and fever. Here are some important factors to better understand its value to your health.

How can aspirin fight heart disease and stroke?

Aspirin fights harmful blood clots. Heart attacks occur when a clot suddenly blocks part of the heart's own blood supply. In most strokes, a clot blocks part of the brain's blood supply.

The clots occur because of atherosclerosis, a disease which clogs the inside of arteries. Aspirin makes it harder for these clots to form. Also, after bypass graft surgery and angioplasty (where a narrowed heart artery is opened up from inside the artery), aspirin reduces the chance of vessels re-clogging.

Should everyone use aspirin for these purposes?

No! Please read on.

Who is likely to benefit from aspirin?

Nearly all people can benefit if they:

  • are in the process of having a heart attack

  • have had an attack and want to prevent another

  • have angina (chest pain from poor blood supply to the heart)

  • have had bypass graft surgery for diseased heart arteries

  • have had angioplasty

Others who can benefit are those who:

  • have had a stroke and want to prevent another

  • have had a temporary 'mini-stroke' (TIA : transient ischaemic attack) and want to prevent a full stroke

  • have a disturbed heart rhythm known as atrial fibrillation

When used for these purposes aspirin is usually taken long term and in low doses.

What about aspirin for other people?

It is still not proven that aspirin prevents heart disease, especially in people at low risk of heart disease and stroke.

Those who may benefit are men aged over 40 who have not had a heart attack or stroke but who are at high risk because they:

  • have other blood vessel problems

  • cannot stop smoking

  • have high blood cholesterol or high blood pressure

  • have a bad family history of heart and blood vessel disease

But no-one should use aspirin for prevention of heart and blood vessel disease unless their doctor clearly recommends they do so.

Should you have a doctor's recommendation before going on aspirin long term?

Yes. Aspirin is generally very safe. But like all drugs it can have side effects and in a small minority of people it might be dangerous. You need a doctor to weigh up the benefits and risks. People who may not be able to take aspirin are those who:

  • have had problems with it before

  • are allergic to it

  • have a stomach or duodenal ulcer

  • have bleeding from the gut

  • have a general tendency to bleed

See 'side effects' below.

Is aspirin enough?

No. All people taking aspirin for heart or blood vessel reasons should also:

  • enjoy healthy eating

  • be smoke free

  • maintain healthy blood pressure, blood cholesterol and body weight

  • be physically active of a level appropriate to their condition

Many of these people may be taking other drugs as well to help control their problems and reduce their risk.

What are the side effects?

Some people on aspirin can experience heartburn, stomach pain, minor bleeding from the stomach and worsening of duodenal or stomach ulcers. In such cases special aspirin preparations may help. There is also a very slight risk of bleeding from the gut or a stroke from bleeding in the brain.

Please note, these side effects and risks are very low with the low doses used. In patients with heart or blood vessel disease, the potential benefit of reducing the risk of a clotting-type stroke usually far outweighs the risk of having a bleeding stroke.

What doses are used?

The recommended daily dose is 75-150 mg ( a standard aspirin tablet is 300-325 mg). Higher doses give no more benefits but they do have more side effects.

When doctors or ambulance staff suspect someone is having a heart attack, they will advise a higher dose of half to one 325 mg tablet taken straight away, preferably the type that can be dissolved in water.

Remember .....

  • don't start aspirin use unless your doctor advises it

  • aspirin is not a cure-all for heart or blood vessel disease

  • follow a healthy lifestyle whether or not you're taking medication

June 1995