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Treating, curing and preventing disease - OCR Gateway The discovery of new drugs

Pathogens are everywhere. The body has evolved defences that act to prevent pathogens entering it. If a pathogen does enter the body then the immune system helps to fight it off.

Part of Biology (Single Science)Global challenges

The discovery of new drugs

New 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 antibiotic penicillin from the Penicillium mould. This antibiotic is still very important in the fight against disease.

A lea of foxglove

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. As many plant species might still contain drugs that are yet to be discovered, it is important that plants are protected.

Once discovered, most plant drugs can be created in a laboratory by scientists at companies. These companies now have versions of the plant extracts, and use these as the starting point to develop new drugs.