Toxicological properties of closantel.

The acute, subacute and chronic toxicity studies in laboratory animals showed that closantel is a well tolerated substance. At multiples of the clinical dose, overdosing might result in central nervous system effects and death. Repeated oral dosing was without effects up to 40 mg/kg in rats and dogs except for focal swelling of the epididymis in male rats at 40 mg/kg due to formation of spermatic granulomas.

Effect of a high dosage of ketoconazole all or not combined with ovariectomy on N-nitroso-N-methylurea-induced mammary cancer in the rat.

Rats bearing mammary carcinomas induced by N-nitroso-N-methylurea (NMU) were subjected to either no treatment (C), to ovariectomy (O), to continuous ketoconazole dosing at 400 ppm into the diet (K) or to both ovariectomy and ketoconazole dosing (O + K). In both C and K groups survival over the experimental period of 15 weeks was low (12.5% and 15.