Prescription under medical supervision

Therapeutic action

– Sulfonamide antibacterial


– Treatment and secondary prophylaxis of toxoplasmosis in immunodeficient patients, in combination with pyrimethamine

Forms and strengths

– 500 mg tablet

Dosage and duration

– Treatment of toxoplasmosis
Adult: 2 g 2 to 3 times daily for 6 weeks minimum

– Secondary prophylaxis of toxoplasmosis
Adult: 1 to 1.5 g 2 times daily, as long as necessary

Contra-indications, adverse effects, precautions

– Do not administer to sulfonamide-allergic patients; patients with severe renal or hepatic impairment.
– May cause:
• gastrointestinal disturbances, renal disorders (crystalluria, etc.), photosensitivity, megaloblastic anaemia due to folic acid deficiency; haemolytic anaemia in patients with G6PD deficiency;
• allergic reactions (fever, rash, etc.) sometimes severe (Lyell's and Stevens-Johnson syndromes, haematological disorders, etc.). In these cases, stop treatment immediately.
– Adverse effects occur more frequently in patients with HIV infection.
– Monitor blood count if possible.
– Reduce the dose by half in patients with renal impairment.
– Do not combine with methotrexate and phenytoin.
– Administer calcium folinate systematically to prevent folic acid deficiency.
– Drink a lot of liquid during treatment.
– Pregnancy: no contra-indication. However, avoid using during the last month of pregnancy (risk of jaundice and haemolytic anaemia in the newborn infant).
– Breast-feeding: avoid if preterm infant, jaundice, low-birth weight, infant under one month of age. If sulfadiazine is used, observe the infant for signs of jaundice.


  Storage: below 25 °C -