A Comparative study of analgesic effects of tramadol and morphine on mice

Pain and inflammation are among those problems that human being are intended to relief or lower it. Application of traditional medicine and using pharmaceutical plants and even Narcotic Materials associated with peritoneal drugs for preventing from pain episodes or relieving it are some resembling examples. Tramadol (Ultram) is a newer synthetic analgesic drug with weak mu () agonist effects and some inhibitory effects on norepinephrine and serotonin reuptake in C.N.S. It is believed to act mainly through an active metabolite that has weak analgesic effects similar to those of propoxyphene. Methods & Materials: In this experimental study 36 mice with similar race and gender with weight range of 20‑25 gr. were chosen and devided into three morphine, tramadol and control groups, then morphine and tramadol were injected intraperitoneally diluted in 0.5cc distilled water for each mouse of first and second groups. After 45 minutes, the cases were assessed under "Tail flick analgesia meter" with 40 º Intensity and Double blind method. According to the study findings there were a significant difference among the three groups pain tolerance time (p<0.05) mean tolerance time was 4.675 in control group, 15.75. with 1,2 and 3 mg/ml in tramadol group respectively. Paying attention to the study results, high concentrations of tramadol is needed to obtain the similar analgesic effects of morphine. As it mentioned above the morphine group with 1mg/ml dose had the same effect as tramadol of 3 mg/ml.