ASPIRIN - The drug of the century

Aspirin, probably the worlds most famous drug, was one hundred years old on 6 March 1999.

At the headquarters of Bayer in Germany where this remedy for pain, fever, colds as well as other innumerable medical conditions, was first discovered, a series of celebrations are planned.

The celebrations will not only focus on Aspirins illustrious history but will bring together medical researchers from around the world who are discovering new applications for this wonder drug.

Today, a new scientific publication on Aspirin is published every two and a half hours. Without doubt, Aspirin is the most researched drug in medical history. Yet when it was first discovered at the end of the last century by the Bayer chemist, Felix Hoffmann, there was little excitement.

As a medicine, Aspirin was perceived as nothing new. For some time, Hoffmans discovery lay buried in a file in the Bayer laboratories. It was only after glowing reports from clinical trials with Aspirin in Berlin hospitals that Bayer decided to do something about it.

This initial reluctance to mass market the drug can be partly explained by the origins of Aspirin itself Salicylic acid, the active ingredient of Aspirin, is obtained from the bark of willow trees. Hippocrates, generally considered the Father of Medicine had noted the pain-relieving qualities of the juice obtained from the willow tree bark around 400 BC.

In the Middle Ages, herb women boiled the willow bark and gave the bitter brew to people plagued by pain until the stripping of willow trees became punishable by law because they were urgently needed by the wicker industry.

Salicylic acid survived only as a popular herbal cure until modern science rediscovered it in the 18th century. A report in the journal of the Royal Society of Medicine in 1763 speaks of the positive results of willow bark when given to 50 feverish patients.

By 1859, salicylic acid had been successfully synthesised in the laboratories so chemists were no longer dependent on plants for the raw ingredient. However there was still a great deal of work to be done before Aspirin could become a reality.

Until Hoffman took up the cudgels in the Bayer laboratories, salicylic acid was undeniably successful in treating rheumatic pain and fever. However, it also had unpleasant side effects which severely limited its use, making patients feel sick and nauseous.

In 1897 Hoffman, working in what was one of the first industrial laboratories, had been searching for an effective drug for rheumatism that could be better tolerated. He was working from the very best of motives he wanted to help his rheumatic father who, like many patients, was reacting badly to the prescribed sodium salicylate.

Hoffmans aim was to refine the salicylic acid and make it tolerable. He ultimately succeeded in this task by acetylation, that is creating a compound of salicylic acid with acetic acid. In an entry in his lab journal dated 10 August 1897, he describes acetylsalicylic acid, ASA for short, which he had synthesised in a chemically pure and non-perishable form.

ASA was the first drug ever to be tested in clinical trials before registration. The results were so positive that Bayer decided to begin production. An application for the Aspirin trade name was submitted on 1 February 1899 and on 6 March 1899, Aspirin was registered as a trade name under the number 36 433 of the Imperial Patent Office in Berlin.

This marked the beginning of Aspirins triumphant march through medical history.

In the 1970s, British pharmacologist, John Vane, was able to determine how ASA takes effect and received the Nobel Prize for Medicine as acknowledgement of his breakthrough research.

Sir John Vanes work was to prove essential in prompting medical science to accept that apart from its pain killing qualities, the decades old folklore that Aspirin could thin the blood had to have a ring of truth.

This theory had begun to be supported by clinical evidence as far back as 1950 when an American doctor, Lawrence Craven had claimed to eliminate all coronary thrombosis among his patients by prescribing Aspirin. He had correctly deduced the principle which explains Aspirins role in fighting other major diseases. By preventing blood clots, Aspirin helps keep open constricted vessels. As most strokes occur when a thrombosis stops oxygen from reaching the brain, regular doses of Aspirin have been shown to reduce strokes by 20 to 35 per cent for high risk patients.

It is more difficult to understand why Aspirin should prevent bowel cancer yet there is clearly grounds for believing it does. A US study has suggested that regular long term use reduces the risk of death from colonic cancer by 44 per cent.

More research needs to be done on the relationship between cancer and Aspirin - just one area of research that scientists all over the world are focusing on.

In 1996 the US Food and Drug Administration, better known as the FDA and one of the most stringent regulatory bodies in the world, recommended extending the range of indications for acetylsalicyclic acid. It recommended it be used not only as a preventive medicine for second heart attacks but also as a treatment for acute infarction. The results of the largest study with patients ever carried out in medical history were the driving force behind this decision.

According to these findings, the miracle drug not only relieves pain, stops inflammation and reduces fever but also works as a prophylaxis against infarction, stroke and a number of related cardiovascular diseases.

It is not only in heart disease that Aspirin is the subject of investigation. The number of clinical trials involving Aspirin continues to increase in number. At the moment, to name only a few, Italian scientists are investigating its use in the prevention of herpes while in New Zealand, trials continue as to whether Aspirin can inhibit the progression of prostate cancer. In the USA, doctors are determining whether Aspirin has a role to play in the artificial fertilisation process in women and in Poland there are trials as to whether Aspirin can assist in early screening for asthma.

Very few drugs from the Victorian pharmacy remain with us today. Yet not only is Aspirin still a feature of our bathroom cabinets and medicine cupboards, its range of uses continues to expand. Worldwide, over 100 billion tablets containing Aspirin are consumed every year and new applications for its use are announced with astonishing regularity.

It is clear there is more to discover about Aspirins healing properties and the likelihood is that one hundred years from now, medical text books will continue to sing the praises of Aspirin, undeniably the Drug of the 20th Century.