Treatment of toxoplasmosis in immunocompetent patients is usually unnecessary. In immunocompromised patients, the recommended treatment is a combination of pyrimethamine given at 25-100 mg daily and trisulfapyrimidines given at 2-6 g daily, both for a month. This drug combination inhibits dihydrofolate reductase in T. gondii, preventing synthesis of DNA and protein. Folinic acid can also be administered to reduce bone marrow depression caused by the pyrimethamine. Clindamycin has been found to be effective at treating toxoplasma encephalitis in AIDS patients.
In acutely infected pregnant women, the recommended treatment includes spiramycin if the fetus has not yet acquired toxoplasmosis. Spiramycin is an antibiotic that localizes to the placenta and has been shown to reduce placental infection by 60%. It does have some teratogenic effects, which must be weighed against the risk of congenital infection. If the fetus is infected, the aforementioned drug combination is administered instead of spiramycin.
John and Petri.
Cohen and Powderly.