Propoxyphene

Propoxyphene (PPX) is a narcotic analgesic compound bearing structural similarity to methadone. As an analgesic, Propoxyphene can be 50-75% as potent as oral codeine. Peak plasma concentrations of Propoxyphene are achieved from 1 to 2 hours post dose. In the case of overdose, Propoxyphene blood concentrations can reach significantly higher levels. In humans, Propoxyphene is metabolized by N-demethylation in liver to yield Norpropoxyphene. Norpropoxyphene has a longer half-life (30 -36 hours) than parent Propoxyphene (6 - 12 hours). The accumulation of Norpropoxyphene seen with repeated doses may be largely responsible for resultant toxicity. This test detects the presence of propoxyphene and its metabolites in human urine specimens, qualitatively.