Evaluation of the antinociceptive effects of tramadol in co-administration with diclofenac intraperitoneally in mice

Abstract

The combination of two analgesic drugs of the same or different class is very used in the therapeutic clinic with the purpose of to harness its effects and to reduce the sequels. In order to evaluate a possible antinociceptive synergistic interaction of diclofenac i.p., a NSAID (nonsteroidal antiinflammatory drug), and tramadol i.p., atypical opioid, were administered by separated and in combination using an immersion model in hot water tail. Female mice were administered with diclofenac (8.1 DE50 mg/kg) and tramadol solo (10, 17, 8.31, 6.56, 2, 100 mg/kg) in an individual way, as well as the coadministration of both DE50. For the data processing was used a Student t test, in which the theoretical sum against the real effect of the coadministration was compared. As a result of the experiment was shown a significant involution of the antinociceptive effect of the coadministration in comparison to the individual administration of both drugs and with the theoretical addition of these was obtained a significant difference too. The synergistic antinociceptive effects of tramadol and diclofenac were important and suggests that combination with these drugs may have a clinical utility in pain therapy.