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.
SIDE EFFECTS WARNING:
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:
- Severe allergic reactions
- Increased blood levels of phenylalanine
- Weight loss
- Reduced number of white blood cells
- Reduced number of platelets
- Swelling of the tongue
- Blood in the urine
- Abnormal heart rhythms
Quick GuideInfectious Mononucleosis (Mono): Symptoms and Treatment
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
Need help identifying pills and medications?
Use the pill identifier tool on RxList.