Primary treatment of Toxoplasma gondii encephalitis in adults
For primary treatment of T. gondii encephalitis in adults, as a 3-drug regimen, use:Panel on guidelines for the prevention and treatment of opportunistic infections in adults and adolescents
pyrimethamine 200 mg orally for the first dose, then 50 mg daily (or 75 mg daily for patients weighing 60 kg or more) for 6 weeks12pyrimethaminepyrimethaminepyrimethamine
PLUS
calcium folinate 15 mg orally, daily for 6 weeks3calcium folinatecalcium folinatecalcium folinate
PLUS EITHER
1sulfadiazine 1 g (or 1.5 g for patients weighing 60 kg or more) orally, 6-hourly for 6 weeks4 15. For dosage adjustment in adults with kidney impairment, see sulfadiazine dosage adjustmentsulfadiazinesulfadiazinesulfadiazine
OR
2clindamycin 600 mg intravenously, 6-hourly for 6 weeks.clindamycinclindamycinclindamycin
For adults with hypersensitivity to trimethoprim+sulfamethoxazole, use clindamycin in the above regimen.
If patients using the clindamycin regimen are tolerating oral pyrimethamine and calcium folinate, consider switching to oral clindamycin. A suitable regimen is:
clindamycin 600 mg orally, 6-hourly for 6 weeks (intravenous + oral).
To support medication adherence on discharge or if the cost of the 3-drug regimen is prohibitive, patients can switch to one of the trimethoprim+sulfamethoxazole regimens below. The 3-drug regimen must be used for at least 2 weeks before switching. Continue trimethoprim+sulfamethoxazole for the total duration of 6 weeks, this includes doses given as a 3-drug regimen.
If the 3-drug regimens above are not appropriate, use:Panel on guidelines for the prevention and treatment of opportunistic infections in adults and adolescents
1trimethoprim+sulfamethoxazole 5+25 mg/kg up to 480+2400 mg orally, 12-hourly for 6 weeks. For dosage adjustment in adults with kidney impairment, see trimethoprim+sulfamethoxazole dosage adjustment. See Calculated dose and number of tablets of trimethoprim+sulfamethoxazole to achieve a 5+25 mg/kg dose in adults for calculated weight-banded doses in number of double-strength tabletstrimethoprim + sulfamethoxazoletrimethoprim+sulfamethoxazoletrimethoprim+sulfamethoxazole
OR if oral therapy is not tolerated
1trimethoprim+sulfamethoxazole 5+25 mg/kg up to 480+2400 mg intravenously, 12-hourly for 6 weeks. For dosage adjustment in adults with kidney impairment, see trimethoprim+sulfamethoxazole dosage adjustment.
If treated with intravenous trimethoprim+sulfamethoxazole, switch to oral therapy once the patient is clinically improving and able to tolerate oral medications.
A combination of pyrimethamine, calcium folinate and atovaquone can be used if none of the above regimens are suitable – seek expert advice.