Sulfadoxine
Sulfadoxine is an ultra-long-lasting sulfonamide used in combination with pyrimethamine to treat malaria.
It is also used to prevent malaria but due to high levels of resistance, this use is becoming less common.
It is also used, usually in combination with other drugs, to treat or prevent various infections in livestock.Sulfadoxine competitively inhibits dihydropteroate synthase, interfering with folate synthesis.