Evidence for a pharmacokinetic interaction between ibuprofen and meptazinol in the mouse

Of a variety of non-steroidal anti-inflammatory drugs administered concurrently with meptazinol (p.o.), only ibuprofen potentiated the antinociceptive response (mouse, hot-plate test) to the opioid. In addition, the brain tritium concentration of mice given [3H]meptazinol (p.o. or i.v.) was significantly raised by the oral administration of ibuprofen. It is argued that the interaction between these drugs is pharmacokinetic in nature, due probably to an action of ibuprofen on the biotransformation of meptazinol.