ASPIRIN

In the days before aspirin, people had to be creative in their approach to pain relief. During the Middle Ages, the beaver - specifically, a gland under its tail - was so sought-after for its sedative properties (as well as its pelt) that it became extinct in this country about 400 years ago.

Plants such as yellow jasmine, Jamaican dogwood, Californian poppies and chilli peppers were all popular, and infusions made with willow bark were a staple folk remedy for hundreds of years.

When, in 1758, a vicar from Chipping Norton in Oxfordshire found that chewing a willow twig helped to ease his headache, he drew up instructions for a formal preparation. But the Reverend Edward Stone’s letters to the authorities went unanswered.

It wasn’t until a century later that scientists synthesised the active ingredient - salicylic acid. But the new drug had two unpleasant side-effects - it irritated the stomach and it tasted bitter. Researchers at a German company, Bayer, discovered that a spoonful of acetyl helped the medicine go down, and in 1899 Herr Felix Hoffman registered “aspirin” as a trade name.

Since then aspirin has gone on to prove its worth in everyday and extraordinary ways. Millions can vouch for its pain-relieving properties, but aspirin is also an antipyretic (temperature lowering) and anti-inflammatory drug. It can be used as a preventative medicine (daily doses can reduce the risk of a heart attack or stroke by thinning the blood) and can also protect against some causes of miscarriage, cancers, cataracts and even dementia. It has also been found to guard some veg-etables against pests.

Like many good things, a little goes a long way and a lot might just go too far. The difference between a therapeutic dose of aspirin and a deadly one is a factor of just 25, compared to 50 for stronger painkillers such as morphine.

Next week, a new law will restrict the aspirin tablets you can buy over the counter to 16, in an attempt to reduce the number of people who use them to take their own lives.