Quinine belongs to a group of medications called the antimalarials. It is used to treat an established malarial infectionMalaria is caused by an organism which classed as a protozoa and is a parasite which is carried by mosquitoes. During a bite from a mosquito, the parasite passes into the body. Once inside, it lives and reproduces. This results in the infection known as malaria.

QQuinine  binds to the genetic material (DNA) of the parasite. DNA is responsible for copying the genetic material which is vital for the replication of the parasite. When quinine binds to DNA this copying process is prevented. This inhibits the reproduction of the parasite and therefore controls the infection allowing the person to recover. Quinine is usually used in the treatment of a type of malaria known as falciparum malaria. It is also used to treat malaria where the type of infecting organism is unknown.