A NEW drug that lowers heart rate and reduces chest pains for heart patients as effectively as standard drugs, but with fewer side effects, was launched here on Tuesday.

Ivabradine promises the greatest benefit to about a third of heart patients who need medication to relieve their chest pains, but for whom standard drugs do not work or cannot be used.

About 4 per cent of the population here, or about 100,000 people, suffer from intermittent episodes of chest pains that usually stem from clogged arteries, known as angina.

Many of them are usually given a type of standard drugs known as beta blockers, which slow down heart rate and eases the pains.

But beta blockers do not work, or are not suitable, for about a third of patients. Asthmatics, for example, cannot use beta blockers as they can cause breathlessness.

Other side effects include fatigue, dizziness, dry mouth, eyes and skin, as well as cold hands and feet, and even depression.

Studies have shown that the new drug, ivabradine, does not result in most of these side effects, so it can be used by such patients, including asthmatics.

The new drug causes about one in 10 users to see flashes of light or feel dizzy, but in most cases, these go away with time.

But it costs much more: about $4 for a day's supply, compared to as cheap as 10 cents a day for older beta blockers.