1 May 2026Oral drugs
Sulfadiazine oral
Sulfadiazine guidance for treatment and secondary prophylaxis of toxoplasmosis in immunodeficient patients.
Prescription under medical supervision
This guide page is for structured reference only and does not replace a clinician, pharmacist, or emergency review. Dose choice, route choice, interactions, and safety decisions still need professional judgment.
Therapeutic action
Sulfonamide antibacterial.
Indications
Treatment and secondary prophylaxis of toxoplasmosis in immunodeficient patients, in combination with pyrimethamine.
Forms and strengths
- 500 mg tablet.
Dose and duration
Treatment of toxoplasmosis
- Adult: 2 g 2 to 3 times daily for a minimum of 6 weeks.
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 or patients with severe renal or hepatic impairment.
- May cause gastrointestinal disturbances, renal disorders, photosensitivity, megaloblastic anaemia due to folic acid deficiency, haemolytic anaemia in patients with G6PD deficiency, and allergic reactions that may be severe.
- 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 during the last month of pregnancy.
- Breast-feeding: avoid if the infant is preterm, jaundiced, low birth weight, or under one month of age.
Source
MSF Essential drugs practical guidelines (January 2026)
This page reproduces the structured reference information for this batch while leaving out the Storage and Remarks sections.
Rate this guide
Be the first to rate this guide.