Evaluation of the sub-chronic oral toxicity of siddha herbo-mineral formulation Kalsiwin tablet

Introduction: To determine the safety index of Siddha herbo-mineral formulation Kalsiwin tablet on chronic oral administration, the sub-chronic oral toxicity studies were carried out by measuring its no-observed-adverse-effect level (NOAEL) and maximum tolerated dose (MTD) in rats. Materials and Methods: The sub-chronic oral toxicity of Kalsiwin was evaluated as per Organization for Economic Cooperation and Development 408 Guidelines in either sex of Wistar rats. Kalsiwin was administered at two dose level one is 45 mg/kg/day as rat dose equivalent to 500 mg adult clinical dose, the other one is 90 mg/kg/day is double the dose level of normal clinical dose to determine MTD. In a sub-chronic study, Kalsiwin was administered 90 days. Mortality, observational, behavioral changes, feed and water consumption, hematological, biochemical parameters, organ weight, histopathology of the liver, kidney, and intestine were observed during the study period. Results: In the sub-chronic administration of Kalsiwin at the therapeutic dose level did not show any severe toxicity symptoms. Higher dose level (90 mg/kg) showed significant changes in the liver biochemical markers and histological changes in the liver, kidney, and intestine. Furthermore, X-ray studies showed renal calculi formation in two out of three male rats treated with a higher dose level of Kalsiwin. Conclusion: The NOAEL of Kalsiwin was 500 mg/day of human therapeutic dose and MTD was less than 1000 mg/day. This study suggested that 500 mg/day adult dose of Kalsiwin is safer on chronic use.