Tramadol Dependence Rate as Compared with Morphine in Rats

Abstract

Abstract: Tramadol is a codeine synthetic analogue that has an affinity to opioid µ receptors, also some evidence show that tramadol has a potency to induce drug dependence, so we conducted to study and compare tramadol dependence with morphine in rats. In this study 30 wistar male rats were randomly divided in to 5 groups: Sham (normal saline), control (increasing doses of morphine), test 1 (fixed dose of tramadol), test 2 (increasing doses of tramadol) and test 3 (first morphine and then tramadol). Two milliliter of each planed administrating regimen were injected intraperitoneally for 10 days, 3.5 h after last injection 5 mg kg of naloxane was injected and withdrawal symptoms were recorded in all groups1 and analyzed as a criterion for dependence. Results showed that both fixed and increasing doses of tramadol induce drug dependence as compared with sham (p<0.05 and p<0.001, respectively). Furthermore the dependence rate in test 1 and test 2 groups was significantly less than control (p<0.05). Although there was a significant dependence rate in test 3 group as compared with sham (p<0.05), but there wasn’t a significant difference between test 3 and control groups. According to our findings and data reported in similar studies tramadol has a relative potency to induce drug dependence, so it is suggested to be more careful in prescribing it as an analgesic. Key words: Tramadol Drug dependence morphine INTRODUCTION MATERIALS AND METHODS Nowadays addiction is an ever-increasing problem in the Thirty adult, male wistar rats weighing 200-250 g were