In sub-acute toxicity studies, the drug is given to animals for

PRECLINICAL TOXICITY STUDIES Acute toxicity studies Single escalating doses are given to small group of animals and the animals are observed for 1-3 days. LD50 is calculated. Organ toxicity is examined by histopathology. Sub-acute toxicity studies Repeated doses of the drug are given for 2-12 weeks. Animal are examined for ove effects, food intake, body weight, hematology Chronic toxicity studies The drug is given for 6-12 months. Animal are examined for ove effects, food intake, body weight, hematology