Morphological changes in the liver on chronic administration of small doses of paracetamol in albino rats.

30 male albino rats of Wistar strain were used to study the effect of repeated administration of small doses of paracetamol over a period of 24 weeks. The animals were administered 0.3 g of paracetamol orally admixed in the diet, after an overnight fast. Three animals from the test group and one control were sacrificed at the end of 4, 8, 12, 16, 20 and 24 weeks, under ether anaesthesia. Liver cell necrosis was not seen at any stage of the experiment. Fatty change was focal at 4 to 8 weeks and diffuse at 12 to 24 weeks. Chronic administration of paracetamol admixed in the diet showed less extensive changes comprising of focal ballooning degeneration. Ultrastructural changes involved mitochondria and RER. Fibrosis was not seen.