Quantitation of Tapentadol by Liquid Chromatography: Tandem Mass Spectrometry.

Tapentadol is an orally active analgesic with a similar structure to tramadol. Its primary mechanism of action is agonist action on the mu-opioid receptor. The method described here quantitates tapentadol in the whole blood using a matching deuterated internal standard, extraction via a protein "crash" with acetonitrile, followed by analysis using liquid chromatography-tandem mass spectrometry.