View source for 12. Drug research and development

How do scientists get ideas for new drugs? In some cases (like opium), they can look to substances that have been used naturally for a long time and use or modify them to suit other needs. However, in most cases, drug development begins by systematically searching for a new molecule that has certain effects. Drug developers can look to already existing drugs and try to modify them to create a new drug with similar, but better effects, or they can try to make molecules that resemble endogenous compounds.

Drugs go through many tests from the time they are first synthesized until they are given to patients. They must be first tested on animals, then tested to see if they are safe for humans, then tested to see if the drug actually has the expected therapeutic effects on humans.

However, these tests are not perfect. It’s impossible to test for all possible side-effects and contraindications, and it’s impossible to know a drugs long-term effect until the drug has been given to patients long-term. The classical example of this is the story of ''thalidomide.''