Uses of chemicals originating from plant defence mechanisms in medicine

Quinine is from the cinchona tree, found in Java and Indonesia. Quinine lowers body temperature and is an effective anti-malarial drug. 

Aspirin is from the willow tree so is found in many locations across the world. The medical substance salicin is used to manufacture the drug. 

Aspirin is a very useful painkiller (anti-inflammatory). It also reduces fever (anti-pyretic) and reduces blood clots (anti-platelet), making it useful for heart attack or stroke victims. 

Taxol comes from the Pacific Yew Tree. It is an anti-cancer drug used in chemotheraphy. 

Both vinblastine and vincristine are sourced from the Rosy Periwinkle, found in tropical rainforests. Both are anti-cancer drugs which reduce cancer cells, used in chemotheraphy. 

Artemisinin is sourced from the Artemisia Annua shrub in China and South East Asia. Artemisinin kills the malaria parasite and prevents reproduction, so is an anti-malarial treatment.