The drug IMAZIN XL is being launched in the week that aspirin celebrates its 100th birthday.

Manufacturers Napp Pharmaceuticals says about one half of the UK's two million angina sufferers do not take aspirin, although it says the drug could save thousands of lives.

The standard treatment for angina, a crushing pain felt in the chest, is drugs containing isosorbide mononitrate.

These help lower blood pressure and prevent angina attacks.

But many people taking isosorbide mononitrates do not take aspirin, which prevents blood clotting.

Fewer drugs to pop

By combining aspirin and isosorbide mononitrate, IMAZIN XL ensures patients will receive both drugs and have fewer pills to pop.

Dr Paul Stillman, a GP from Crawley, said: "IMAZIN XL helps prevent angina and offers long-term protection against heart attack. This new formulation benefits doctors, patients and the NHS."

However, the drug does cause temporary side effects in some patients, including low blood pressure and headaches.

Cambridge-based Napp Pharmaceuticals says it should also not be taken by people with acute angina or kidney and liver failure.

Many studies have shown that aspirin substantially reduces the risk of death or non-fatal heart attacks in patients with a previous MI or unstable angina pectoris, which often occurs before a heart attack.

The Antiplateletes Trialists' Collaboration, which reviewed 145 studies on the role of aspirin in preventing heart attack and stroke, found the drug reduced the risk of non-fatal heart attack by a third.

But there are concerns that aspirin could cause internal bleeding and ulcers if taken in too high doses.

A small number of people are hypersensitive to the drug and cannot tolerate even small amounts.

In higher doses aspirin can cause nausea, heartburn and stomach pain. In a small number of people it can cause cerebral haemorrhage.

Heart attack risk

According to medical statistics, one angina sufferer in 10 will suffer a heart attack within a year of being diagnosed with angina.

Angina, which is more common in men than women, is caused by a decrease in blood supply to the heart.

This is usually the result of a narrowing of the coronary arteries, due to smoking, being overweight, high blood pressure, too much cholesterol, a family history of heart disease or being unfit.