New drugs need to be tested and trialled before doctors prescribe them and patients take them. This allows drugs to be checked for:
|Safety||Some drugs are toxic, and have other side effects that might be harmful to people|
|Effectiveness||Checks how well the drug cures the disease, or improves symptoms|
|Dosage||This varies, and has to be closely controlled, as too high a concentration might be toxic|
There are three main stages of testing:
There are obvious benefits to testing drugs but some people consider drug trials to be dangerous and animal testing to be unethical.
Thalidomide is a medical drug that caused unexpected and serious damage to unborn babies in the 1950s and 1960s. Thalidomide was developed as a sleeping pill, but it was also thought to be useful for easing morning sickness in pregnant women. Unfortunately, it had not been tested for use in this way.
By 1960 thalidomide was found to damage the development of unborn babies, especially if it had been taken in the first four to eight weeks of pregnancy. The drug led to the arms or legs of the babies being very short or incompletely formed. More than 10,000 babies were affected around the world. As a result of this disaster, thalidomide was banned. Drug testing was also made more rigorous than before.
Thalidomide is now used as a treatment for leprosy and bone cancer. Its use is heavily regulated, however, to prevent a repeat of the problems it caused in the last century.