Bioavailability of D‐Propoxyphene, Acetyl Salicylic Acid, and Phenazone in a Combination Tablet (Doleron®): Interindividual Variation and Influence of Food Intake

Abstract

The influence of food intake on bioavailability of 3 analgesic compounds (propoxyphene chloride, acetylsalicylic acid and phenazone) in a combination tablet, Doleron, was examined in 8 healthy volunteers. A single oral dose was given on an empty stomach and together with a standardized breakfast meal. Plasma concentrations of propoxyphene, its major metabolite norpropoxyphene, salicylic acid and phenazone were determined by mass fragmentography, spectrofluorimetry and gas chromatography. Concomitant food intake had no consistent influence on bioavailability of any of the components. Doleron may be taken together with meals and between meals. Large interindividual variations in propoxyphene and phenazone concentrations were found, indicating that an optimal effect is not always obtained by standard doses.