In Sarawak, the Penan people use over 50 medicinal plants which they harvest from the primary forest - plants that are used as poison antidotes, contraceptives, clot ting agents, general tonics, stimulants, disinfectants, remedies for headaches, fever, cuts and bruises, boils, snake bite, toothache, diarrhea, skin infections and rashes, and for setting bones.

Plants discovered in rainforests also supply western medicine with important drugs: a medicine for malaria (the bark of the cinchona tree produces quinine); a muscle relaxant during surgery (curare, a vine extract used by indigenous peoples to poison arrows and darts); a treatment for depression (secretions of an Amazonian frog can be used to make a useful medicine).

Other products can also be obtained from the rainforest without destroying it. In the rainforests, there are trees that yield 300 kilograms of oil-rich seeds a year, there is a fruit with more vitamin C than an orange, a palm with more vitamin A than spinach and another palm whose seeds contain 27% protein. Yet another tree produces resin that can be used unprocessed to run a diesel engine.