Background: Orlistat is one of the drugs used for treatment of obesity. It acts by preventing the absorption of fats from the human diet by acting as lipase inhibitor. The aim of this work is to determine the effect of administration of orlistat on the liver and the role of vitamin C as a protective agent. Material and methods: 21 rats were used and divided into 3 groups, each group consists of 7 rats: Group 1 (G1): Healthy control rats , Group 2 (G2): Rats received orlistat dissolved in fish oil orally by a gastric tube at a dose of 32 mg/kg b.w/day (9), and Group 3 ( G3): Rats received orlistat dissolved in fish oil orally by a gastric tube at a dose of (32 mg/kg b.w./day), and vitamin C (5mg/kg b.w./day). Treatment was done once daily for a continuous 30 days. Liver sections were examined by light and electron microscope. Results were in the form of cellular vacuolations, shrunken, and condensed nuclei, monocellular infiltration and congestion of portal and central veins. Statistical analysis showed that there was marked dilatation in the central vein in group II which became more or less normal in group III. There was an obvious amelioration in these changes in the group treated with vitamin C.
Conclusion: Clinicians should be aware and carefully monitor their patients on orlistat medication for signs of hepatic dysfunction. The administration of vitamin C might protect against the liver damage produced by orlistat.
Key words: liver, orlistat, congestion, inflammatory cells,adult male albino rats