pyrimethamine (Daraprim)

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GENERIC NAME: pyrimethamine

BRAND NAME: Daraprim

DRUG CLASS AND MECHANISM: Pyrimethamine is an oral antiparasitic drug used for treating Toxoplasma gondii and plasmodia infections. Toxoplasma gondii is a parasite that causes toxoplasmosis, and plasmodia parasites cause malaria. Pyrimethamine prevents parasites from producing important proteins by blocking the use of folic acid which is necessary for the production of proteins. Preventing parasites from producing important proteins prevents growth and development of new parasites. The FDA approved pyrimethamine in January 1953.

PRESCRIBED FOR: Pyrimethamine is used for the treatment of toxoplasmosis and acute malaria when combined with a sulfonamide (for example, sulfadoxine). It also may be used for prevention of malaria, however, resistance of malaria to pyrimethamine is common, and it is not effective for malaria prevention for travelers to most geographic areas.


The dosage of pyrimethamine for treatment of toxoplasmosis is 10 to 20 times the recommended antimalarial dose and is near the toxic level. Signs of folate deficiency may be treated with folic acid (leucovorin) 5 to 15 mg daily until normal blood cell production is restored.

Pyrimethamine may cause cancer.

Pyrimethamine should be kept out of the reach of infants and children. Deaths have been reported after accidental ingestion by pediatric patients.

SIDE EFFECTS: Side effects of pyrimethamine include:

Medically Reviewed by a Doctor on 10/12/2015

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