Pyrimethamine is also used to treat AIDS-related diarrhea and as one of a combination of drugs to treat Toxoplasma gondii, a protozoal infection. People can become infected with the toxo organism by coming in contact with feces, frequently found in dirt. Symptoms include headaches, fever, confusion, lack of energy, and, in some cases, inflammation of parts of the eyes. Toxo can also cause loss of mental status, seizures and paralysis.
Toxoplasmosis can become resistant or unresponsive to existing treatments.
Side effects Folic acid deficiency can cause a painful burning tongue, loss of taste, and anemia. Other side effects can be skin rash, fever, nervousness, loss of appetite, nausea, vomiting, diarrhea, bone marrow depression, and jaundice. Dosage Pyrimethamine comes in tablets combined with sulfad oxine called Fansidar. For treatment of Isosporiasis infection, adults take 50-75 mg of pyrimethamine daily, as needed to control or eliminate infection. For treatment of toxoplasmosis, usual dose is 25 mg daily.