Considering it emerged from the same stable as heroin, aspirin has lived to a surprisingly respectable old age. A hundred years after its birth in a Bayer laboratory, the little white pill is going as strong as ever, albeit in a new direction.
In the 1960s it was in danger of being run off the pain-relief block by newer arrivals like acetaminophin and ibuprofen, which one Dublin pharmacy estimated yesterday were outselling aspirin by 10 to one.
The crucial difference is that aspirin has now established itself as an agent against heart attack and stroke.
Back in the 1920s, Bayer still advertised its pill with the assurance that it "does not affect the heart", but a series of studies has suggested that aspirin slows the ability of blood platelets to form clots.
Prescribed at a much lower dosage than in its pain-relieving form, regular use of the drug is thought to reduce the risk of repeat heart attack by a fifth.
Furthermore, according to the latest issue of Newsweek, the US Food and Drug Administration is expected soon to approve its use to prevent a first heart attack in high-risk groups.
Bayer's statistics show that prevention of heart disease now accounts for 37 per cent of aspirin use, with 23 per cent of people taking it for arthritis. Old-fashioned ailments like headache (14 per cent), body ache (12 per cent) and other pain (14 per cent) trail some distance behind.
Knowledge of the pain-relieving properties of salicylic acid goes back more than 2,000 years, to the father of medicine himself. At any rate, Hippocrates knew that juice from the bark of willow trees, which contains the acid, could be used to treat pain.
Up to the Middle Ages, herbalists still boiled willow bark for this reason, until the needs of the wicker industry caused the stripping of the trees to be outlawed.
The revival of the practice can be credited to Napoleon, whose continental blockade of 1806 stymied the export of quinine from Peru to Europe. An alternative pain-reliever had to be found and scientists turned back to the traditional source.
It was a pan-European effort. In 1828 a Munich pharmacologist, Johann Buchner, boiled willow bark into a yellow substance he called salacin. A year later, in France, the substance was converted to crystal form and Italy refined salacin to form salicylic acid.
Acetylsalicylic acid (ASA) was finally produced in Strasbourg in 1853, but it was chemically impure and could not be preserved. And it took the work of another German chemist, Herman Kolbe, before the drug could be synthesied for industrial production in 1874.
The synthetic product was offered at a tenth of the price of naturally-produced salicylic acid: but it tasted awful, and often had what was described as an "aggressive effect" on the mucous membranes.
It is possibly down to Felix Hoffman's father that the drug was finally produced in a palatable and stable form. Hoffman snr was crippled with rheumatoid arthritis, and the existing medicines were having a severe effect on his stomach. His 29year-old son, a chemist with Bayer, synthesised ASA in a form that was more acceptable to stomachs. And the rest is history.
The late 20th century brought the effervescent tablet; the chewable version; and finally the enteric-coated, low-dosage form for heart treatment, in 1992. In its various forms, the company now produces 11 billion tablets a year for sale in more than 70 countries. Sales in 1996 were worth more than £320 million.
Aspirin is still not for everyone, even those with heart disease. Between 2 and 6 per cent of the population are liable to gastric upset from taking the drug. Indeed, while the Harvard School of Public Health estimates that 10,000 premature American deaths could be avoided each year if heart attack survivors took regular aspirin, other figures show that 17,000 Americans died last year of gastric bleeding, just from taking aspirin or other non-steroid anti-inflamatory drugs, like ibuprofen.
But aspirin may still be a victim of its own success. The Harvard professor who estimated the 10,000 potential life-savings thinks "if aspirin were half as effective and 10 times more expensive people would take it more seriously".
As it sets out on its second century, Bayer is now citing studies which suggest ASA can reduce the risk of colon cancer. And 3,500 scientific papers a year are devoted to probing the drug's uses.
So the omens are good, if you ignore the one provided by Bayer's latest house magazine. At the opening of its facility in Mexico, the caption tells us Bayer's chairman is being shown the new plant by "Dr Ralph Sick".
FactfileName: acetylsalicylic acidBetter known as: aspirinOccupation: pain reliever (semi-retired), heart disease prophylacticWhy it's in the news: it celebrated its 100th birthday this week
