[The dynamics of drug release from suppositories. Part 2: Phenylpyrazolone derivatives in animal experimentation...

The authors studied the in vivo absorption of aminophenazone and aminoantipyrine from suppositories produced by means of, respectively, hydrophilic vehicles (PEG 1000, PEG 1500, PEG 2800, PEG 4000, PEG 5000) and lipophil vehicles (Witepsol H 15 and cocoa butter). It was found that the above-mentioned drugs were absorbed more rapidly from the suppositories with a hydrophilic vehicle than from those with a lipophil vehicle. The absorption time decreased with the increase in molecular mass of the polyethylene glycols used. The absorption times of the two drugs from suppositories with cocoa butter and Witepsol H 15 were relatively short. A correlation has been established between in vitro release and in vivo absorption.