The influence of Trypanosoma congolense infection on the disposition kinetics of diminazene aceturate in the dog.

Diminazene aceturate was administered intravenously at 3.5 mg/kg body weight to mongrel dogs before and after infection with Trypanosoma congolense. Plasma and urine were collected at varying intervals thereafter and analysed for the compound. The mean area under the concentration-time curve (AUC) of diminazene in healthy dogs was 25.8 h.micrograms/ml but was significantly increased (p less than 0.05) to 35.7 h.micrograms/ml after infection with T. congolense. The distribution half-life was significantly reduced (p less than 0.05) in dogs after infection, being 0.12 h compared to 0.17 h in the same dogs before infection. The mean proportion of the diminazene recovered in the urine of infected dogs (25.1%) was not significantly different from that recovered in the urine of healthy dogs (26.8%). These results indicate that infection with T. congolense increases the rate at which diminazene is distributed in the body but that the infection has no marked influence on the urinary excretion of the drug.