Drug Characteristics
  • Formulation

    Tablet: 25 mg

  • Dose

    Toxoplasmosis treatment:

    A loading dose of 200 mg for day 1 then 75 mg (>60kg) orally once a day for up to 6 weeks (in combination with sulfadiazine or clindamycin) and folinic acid 15–30 mg daily

    Toxoplasmosis maintenance:

    25 mg orally once a day (in combination with sulphadiazine or clindamycin) and folinic acid 15 mg daily

    PCP prophylaxis:

    25 mg orally three times a week or 50 mg once each week (in combination with dapsone)

    Toxoplasmosis primary prophylaxis:

    Should be considered for patients with CD4 <200 and positive toxoplasma serology at 50 mg once each week

    Other information: Folinic acid 15 mg orally once a day should always be co-prescribed with daily dosing of pyrimethamine

  • Side Effects

    Neutropenia; thrombocytopenia; macrocytic anaemia; rash

  • Interactions

    Additive toxicity with other bone marrow suppressive drugs e.g. ganciclovir, cotrimoxazole, and zidovudine

  • Renal

    There are limited data in renal impairment as it is principally metabolized in the liver

    Dose in renal impairment : GFR (ml/min)

    20–50: Dose as in normal renal function

    10–20: Dose as in normal renal function

    <10: Dose as in normal renal function

  • Hepatic

    No data on specific dosage reduction in hepatically impaired patients

    Monitor LFTS

  • Pregnancy

    Compatible – Maternal Benefit greater than Embryo-Foetal Risk

  • Other Information