Drug Solvent ID50a
(mg/ml)
TD50b
(mg/ml)
TIc
Valproic acid ethanol 4.5 62.4 13.9
Sodium valproate ethanol 4.1 52 12.7
Carbamazepine ethanol 72 100 1.3
Litium carbonate 1 N HCl > 100 > 100  
Haloperidol ethanol 5.6 103 18.4
9-OH-Risperidone tartaric acid 20.1 134 6.7
Risperidone tartaric acid 74 129 1.7
Fluphenazine HCl Toxo CGM 3.5 17.9 5.1
Clozapine ethanol 5.8 20 3.4
Olanzapine DMSO 33.2 100 3.0
Chlorpromazine HCl DMSO 2.6 6 2.3
Quetiapine fumarate DMSO 18.6 33 1.8
Trimethoprim DMSO 5.3 63.8 12.1
aMedian inhibitory dose, a measure of tachyzoite inhibition; bMedian toxicity dose,a measure of cytotoxicity; cTherapeutic index, a measure of efficacy determined by TD50/ID50 ratio. DMSO, dimethylsulfoxide; Toxo CGM, Toxoplasma cell growth medium. Valproic acid at a concentration of 1 μg/ml inhibited 7% of the tachyzoites and trimethoprim at 3.2 μg/ml produced 2% inhibition, but the combination of these two compounds at those concentrations resulted in a potentiating effect inhibiting 55% of the tachyzoites
Table 43: Drugs tested for in vitro activity against T. gondii (according to Jones- Brando et al. [801]; with own modification).