ABSTRACT
Ultram [Tramadol] is a widely used opioid analgesic effective in treating both acute and chronic pains and has acceptable adverse effects. The aim of the present study was to evaluate the cerebrocortical toxicity resulting from one month and two month Ultram administration in to albino rats using biochemical and histological parameters. The study was carried out on 25 adult male albino rats divided into: control group received 0.5 ml /day saline orally by orogastric tube for two months, a short-term Ultram-treated group that received a dose of 30 mg/kg/day [1/10 LD50] for one month orally and a long-term Ultram-treated group that received the same dose for two months. The study revealed that Ultram administration caused a significant elevation of serotonin level in the cerebral cortical tissues of rats which was directly proportional to the duration of Ultram admistration. Histologically, there were many changes in the organization and ultrastructure of neurons in the different layers of cerebral cortex associated with an increased response of the supporting neuroglial cells. Intense neurological tissue lesions were more evident with the two months Ultram dosing than with one month. The correlation between the biochemical results and the histological findings proved that Ultram induced neuronal lesions could be mediated by the elevated cerebrocortical serotonin level which gives serious alarms for reconsidering the rush towards the excessive use of ultram