Dextropropoxyphene Theophylline

Noninterfering aspirin, caffeine, chlordiazepoxide, dextropropoxyphene, diazepam, lig-nocaine, naloxone, norcodeine, normorphine, papaverine, procaine, quinine, theobromine, theophylline... 

Dextropropoxyphene does not significantly alter steady-state theophylline levels. 

In 6 healthy subjects pre-treatment with dextropropoxyphene 65 mg every 8 hours for 5 days did not significantly change the total plasma clearance of steady-state theophylline 125 mg every 8 hours. There was a small reduction in the formation of the hydroxylated metabolite of theophylline. There would seem to be no need to avoid concurrent use or to take particular precautions. 

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