Acute, subacute and subchronic toxicity of besulpamide

The acute oral and intraperitoneal toxicity of besulpamide has been studied in the rat and mouse, together with the subacute and subchronic oral toxicity in the rat at doses of 0, 125, 500 and 2000 mg/kg/day. The LD50 is in excess of 12,800 mg/kg by the oral route and in excess of 5,000 mg/kg intraperitoneally. Toxic signs were very slight and autopsy did not reveal lesions which could be attributed to the test substance. In the subacute and subchronic toxicities the characteristic effects of the diuretic activity were observed. In the subchronic toxicity study significant, although not dose-related, increases were observed in calcium, alkaline phosphatase, GPT and GOT levels. A decrease in liver-weight of the female animals with respect to controls was also noted. Histopathological studies did not reveal any changes which could be attributed to administration of the test substance. Besulpamide has demonstrated the typical effects of diuretics which are derivatives of 3-sulfamoyl-4-chlorobenzoic acid and in acute, subacute and subchronic tests by the oral route in the rat it has shown itself to be a substance of very low toxicity.