Analgesia by Nonopiate Analgesics May Not Necessarily Depend on Prostaglandin Synthesis Inhibition

Abstract

Nonopioid analgesics are believed to exert their anti-inflammatory and analgesic activities via inhibition of the cyclo-oxygenase system particularly in inflamed tissue. However, there is no satisfying correlation between prostaglandin (PG) synthesis inhibition and analgesic effects. Investigating flurbiprofen, a chiral 2-arylpropionic acid derivative, were obtained evidence that PG synthesis inhibition is mediating the anti-inflammatory activity (S-enantiomer), but that PG synthesis independent mechanisms contribute to the analgesic effects (R-enantiomer). Nevertheless, it cannot be excluded that a reduction of the PG synthesis within the CNS by nonopioid analgesics mediates the analgesic effect observed.