Propoxyphene

Interpretation

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.

Notes:

• 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.

Metabolites

• Propoxyphene is metabolized to norpropoxyphene.
  
  

  Propoxyphene → Norpropoxyphene

Approximate Detection Times

Propoxyphene	LOQ (ng/mL)	Detection Time* up to
Propoxyphene	300	10 days
Norpropoxyphene	300	3 days

*These are approximate detection times for the drug or metabolites in urine. The actual detection time depends on dose, frequency of use, and individual metabolism.