The discovery of new drugs
New A substance that can change chemical reactions in the body. are being developed all the time. Historically drugs have come from nature, as parts of plants and microorganisms have been extracted. One of the most famous discoveries was made by Sir Alexander Fleming, who discovered the Substance that controls the spread of bacteria in the body by killing them or stopping them reproducing. penicillin from the penicillium mould. By chance, he discovered that where an agar plate of bacteria had been contaminated by a mould, the bacteria had been killed.
Antibiotics are still very important in the fight against disease.
Plant extracts
Certain drugs can be extracted from natural sources, and have been known about for a long time. For example, willow bark was used by the ancient Greeks to help cure fevers and pains. It was later discovered that the active ingredient was salicylic acid. This was modified by chemists into the substance we call aspirin, which is less irritating to the stomach than salicylic acid. Another example is the heart drug, digitalis which is extracted from foxgloves.
Plants are still important today, but most drugs are now created in a laboratory by scientists at Relating to medicines and drugs, and their production, sale and use. companies. These companies now have A material made by a chemical process, not naturally occurring. versions of the plant extracts, and use these as the starting point to develop new drugs.