Animal experiment:

Carworth Farms CF-1 mice, 4 to 6 weeks of age, weighing 19 to 22 g are used in this study. The mice are infected by intraperitoneal injection of the several bacteria strains. Sulfasymazine is administered either in the diet or in a single dose by gavage. With the drug-diet method, each group of 10 mice is permitted to feed at will from 1 day before infection to 6 days after infection from a common hopper containing Sulfasymazine uniformly mixed with ground Wayne Mouse Blox. The mice are kept under conditions of alternating 3 h periods of light and dark, in order to encourage eating at more or less regular intervals throughout each 24-h period. Drug intakes, as mg per kg of body weight per day, are determined by calculations based on the initial average weight of the mice, the total diet consumed during the treatment period, and the concentration of drug in the diet[1].

Sulfasymazine is a sulfonamide drug and displays antibacterial properties.

Sulfasymazine is a sulfonamide drug and displays antibacterial properties. On a dosage basis, Sulfasymazine is from 2 to 10 times more potent than sulfisoxazole; on a blood level basis, Sulfasymazine potency ranges from 0.3 to 1. In acute toxicity studies in mice, the sodium salt of Sulfasymazine is tolerated at 2000 mg/kg orally, and at 1000 mg/kg intraperitoneally[1].

[1]. Redin GS, et al. An evaluation of sulfasymazine in infections in mice. Chemotherapy. 1966;11(6):309-14.