SP is a combination drug which inhibits the dihydrofolate reductase (dhfr) and dihydropteroate synthetase (dhps) enzymes in the folate pathway of the parasite, and is widely used as intermittent preventive treatment of malaria in pregnancy (IPTp) and in infants as part of seasonal malaria chemoprophylaxis (SMC) in sub-Saharan Africa. Here, DHFR is linked to malaria.