A risky business

Sometimes things don't always turn out the way we expect. However carefully a drug is researched, developed and tested, things can and do go wrong for some patients. Recent research in the US has claimed that adverse drug reactions may be responsible for the deaths of as many as 100,000 patients in US hospitals each year. But there is not a single therapeutic agent from the most toxic substance to the most innocuous-seeming herbal remedy that does not have the potential to cause an unexpected and undesired reaction in some people.

The human organism is not a series of neat, compartmentalised systems. Add something to the mix, and there is always the risk that it will have knock-on effects on parts that were not being targeted. In the main, these side-effects are usually minor and are far outweighed by the benefits of the treatment, but occasionally they can be dangerous and even fatal.

Sometimes the side-effects can even be beneficial. The most commonly used analgesics, aspirin and ibuprofen - both available over the counter - are thought to have a range of additional advantages, reducing the risks of everything from blood clots to breast, lung, prostate and colon cancer.

Unfortunately, some of the rarer and more serious side-effects appear only once a drug is in widespread use, and even with the most organised reporting system it may be months or even years before action can be taken to prevent widespread damage to the patient population.

In the last couple of months in the UK there have been warnings that, with the exception of Prozac (fluoxetine), SSRIs should not be prescribed to under-18s because of the risk of causing suicidal feelings. It is estimated that some 20,000 children and teenagers will be affected by the recommendation.

This time a year ago, Sars was being cited as one of the most dangerous new diseases affecting humans, and development of a medicine to effect a cure was given the highest priority. Yet now it appears that many recovered patients in China who were treated with strong doses of corticosteroids have developed avascular necrosis of the hips, a bone degeneration condition.

Regrettably, in today's litigation-happy culture the first response to such incidents is to find someone to blame - usually the drug manufacturer for putting an unsafe product onto the market. But often it is the doctor who prescribes a medicine inappropriately - none of the SSRIs, for instance, was indicated for patients under the age of 18. And sometimes, as in the case of the Chinese Sars victims, administering a high-risk therapy is deemed worth the risk in view of the potentially fatal outcome.

In the words of 20th century Austrian economist Ludwig von Mises, 'science does not give us absolute and final certainty. It only gives us assurance within the limits of our mental abilities and the prevailing state of scientific thought.'

In the context of the level of risk that surrounds even the most mundane of our everyday activities, taking a properly prescribed medication is still one of the safest things we can do.