Developing new drugs
Before medical drugs can be sold or prescribed they must be tested to see if they are safe and work. These are the stages of development:
1) Computer models and human cells (grown in a laboratory) test them.
2) The few drugs which pass this step are tested on animals to predict any possible side effects that they could give a human.
3) When the drugs pass these tests clinical trials on healthy volunteers are carried out. To start with only a small dosage is used, but this is increased to find the optimum dosage.
Drug development is very expensive and takes a long time, but can make a lot of money in the long term if successful, and it can save lives, however the clinical trials are dangerous.