This medicine is an antimalarial. It is used to treat a certain type of malaria infection in adults and children who weigh at least 5 kg. Artefan 20/120 contains two antimalarial drugs, artemether and lumefantrine in fixed dose, which work together to kill the malaria parasite (a tiny organism that is found inside the red blood cells). Your doctor has found that you have malaria and so has prescribed Artefan 20/120. It is indicated only for the treatment of so called uncomplicated malarial attacks due to Plasmodium falciparum (a particular type of malaria parasite) against which the medicine is active. For complete cure it is important that you complete the prescribed dose as advised by your doctor, pharmacist or health care provider.