TABLE 2

Treatment of toxoplasmosis in immunocompromised patients

Induction therapyMaintenance therapyComments
For those with body wt of ≥60 kg, pyrimethamine (200 mg once and then 75 mg daily) plus sulfadiazine (1.5 g q6h) plus folinic acid (10–50 mg daily)Pyrimethamine (50 mg daily) plus sulfadiazine (1 g q6h) plus folinic acid (10–25 mg daily)Blood counts, creatinine, and liver function should be monitored regularly
Adequate hydration should be ensured to prevent renal damage from crystalluria
For those with body wt of <60 kg, pyrimethamine (200 mg once and then 50 mg daily) plus sulfadiazine (1 g q6h) plus folinic acid (10–50 mg daily)Pyrimethamine (25 mg daily) plus sulfadiazine (0.5 g q6h) plus folinic acid (10–25 mg daily)Blood counts, creatinine, and liver function should be monitored regularly
Adequate hydration should be ensured to prevent renal damage from crystalluria
Pyrimethamine plus folinic acid (dosing as described above) plus clindamycin (600 mg q6h)Pyrimethamine plus folinic acid (dosing as described above) plus clindamycin (600 mg q8h)Blood counts should be monitored regularly
Clindamycin may cause diarrhea, including Clostridium difficile infection
TMP-SMX (10/50 mg/kg/daya in divided doses)TMP-SMX (5/25 mg/kg/day in divided doses)Blood counts, creatinine, and liver function should be monitored regularly
Adequate hydration should be ensured to prevent renal damage from crystalluria
Atovaquone (1,500 mg twice daily) ± pyrimethamine plus folinic acid (dosing as described above)Atovaquone (750–1,500 mg twice daily) ± pyrimethamine plus folinic acid (dosing as described above)Blood counts and liver function should be monitored regularly
Atovaquone suspension should be taken with a high-fat diet to optimize bioavailability
Atovaquone plus sulfadiazine (dosing as described above)Atovaquone plus sulfadiazine (dosing as described above)Blood counts, creatinine, and liver function should be monitored regularly
Atovaquone suspension should be taken with a high-fat diet to optimize bioavailability
Pyrimethamine plus folinic acid (dosing as described above) plus azithromycinb (1,000 mg daily)Pyrimethamine plus azithromycin not recommended due to a high relapse rate; one of the above regimens should be used insteadBlood counts should be monitored regularly
Azithromycin may cause hearing problems and a prolonged QT interval
  • a Higher doses of 15/75 or 20/100 mg/kg/day can be used.

  • b Clarithromycin can be used instead of azithromycin but is associated with more GI intolerance and drug interactions. If used, a lower dose of 500 mg twice a day is preferred, especially in HIV-infected patients; the efficacy of this dosing regimen is not clear (see the text for details).