Enhancement of Antinociception but not Constipation by Combinations Containing Tramadol and Metamizole in Arthritic Rats

The use of a combination of analgesics could provide an optimal pain treatment with minimal side effects. Combinations of tramadol and some nonsteroidal anti-inflammatory drugs have demonstrated synergistic antinociceptive effects as well as a significantly reduced occurrence of adverse effects. The purpose of this study was to investigate the antinociceptive and constipation effects of tramadol and metamizole alone or in combination in rats and...