The clearance half-life of propoxyphene averages 10 hours. The clearance half-life of norpropoxyphene averages 30 hours. Following a typical 0.2 mg dose of propoxyphene, the drug appears in the urine within 30 minutes. Peak urine output is reached at about 2 hours.
- The presence of propoxyphene >LOQ indicates exposure to propoxyphene for 2 to 3 days prior to specimen collection.
- The presence of the propoxyphene metabolite norpropoxyphene >LOQ indicates exposure to propoxyphene within 7 to 10 days prior to specimen collection.
- Propoxyphene is metabolized to norpropoxyphene.
Propoxyphene → Norpropoxyphene
Approximate Detection Times
|Propoxyphene||LOQ (ng/mL)||Detection Time* up to|