<![CDATA[Background: Repeated and long treatment with tramadol that could cause toxic metabolites by accumulationin the body and with high level of risk of pharmokinetic interaction alongside the decreasing of tramadol,therefore this study was carried out to investigate the toxic impact of the tramadol on the tissues of the brainin the male rats.Method: This experiment was accomplished and processed at environmental toxicology laboratory,environmental studies department, institute of graduate studies and research, university of Alexandria, Alexandriap) ovince, Egypt. a group of rats (32, male) from Albano waster subspecies and they weigh from 200-250g,all belonging to the animal house of the faculty of medicine, university of Alexandria and grouping in tofour groups (8 rats for each group in each cage). In regards to the control group, they were given basal foodand tap water through-out 10 days by gastric tube, day by day. Group three the rats were fed with basal dietand given Tramadol HCL orally in dose 45mg/ kg .B.W dissolved in (5ml) normal saline (0.9%) by gastrictube, daily for Twenty days. Group for the rats were fed with basal diet and given Tramadol HCL orally indose 45mg/ kg .B.W dissolved in (5ml) normal saline (0.9%) by gastric tube, daily for Thirty days. When theexperimental period reached its end, kidney tissues of each rat were instantly removed and after that weighed thenput into 10 percent of neutral buffer formalin to be considered as a fixative solution.The Results: The results showed significantly decrease in the heaviness of the brain in the groups of therats that given the Tramadol HCL in dose 45mg/ kg .B.W with increasing the time of administration ascompared to the control group. Histopathological changes were observed in rats brain tissues section therats that given Tramadol HCL orally in dose 45mg/ kg .B.W dissolved in (5ml) normal saline for ten daysrevealed mild degree of tissue injury in the cerebral cortex, with few vacuolar degeneration and dilatationof blood vessels, and the tissue sections of group two after ten days revealed mild degree of tissue injury inthe cerebral cortex, with few vacuolar degeneration and dilatation of blood vessels, while the three groupObserved increase in the vacuolar degeneration, with neural atrophy and degeneration of neurons withreduction the neural process and pyknosis of the nuclei dilatation of blood vessels after twenty days oftramadol administration. The tissue Sections the obtained from the group four after thirty days revealedincrease in the vacuolar degeneration, with more atrophy of the neural cells and complete reduction theneural process and pyknosis of the nucleus in the injured neural cells and glyosis.The Conclusion of this study there are harmful toxic effects when administrated the tramadol for longperiod on the brain tissues, therefore abuse of tramadol should be avoided except with medical prescriptionowing to its toxic effects.]]>
