[Bamifylline. Conditions of its interference in the estimation of urinary 17-oxosteroids. Method of estimation using Zimmermann's reaction (author's transl)].

Bamifylline in therapeutic dosage may markedly disturb the determination of urinary 17-oxosteroids by Zimmermann's reaction, although the conditions of extraction and formation of this chromogenic substance are not always optimal for the metabolites of bamifylline. It is easy to suspect this interference as the chromogenic substance is produced as soon as the reagents are introduced, contrary to 17-oxosteroids, and it presents a more bluish colour. It is possible to separate completely both types of metabolite by washing the chloroform extracts with acid solutions which form salts with bamifylline and thus extract it. From these acid solutions, bamifylline may be recovered and estimated Zimmermann's reaction which is, for this purpose, modified.