[Bioavailability of theophylline after oral administration of a retard preparation of theophylline-ethylenediamine and the influence of 15-day ingestion on elimination kinetics after i.v. injection (author's transl)]

Abstract

After the administration of 350 mg a retard preparation of theophylline-ethylenediamine (Aminophyllin retard) p.o. to 10 healthy test persons the absorption rate of theophylline amounted to an average of 84%, after which the absorption had not been fully completed in all persons after 10 h. Constant plasma levels appeared under the continuous administration of 350 mg of the retard preparation twice a day after 3-5 d; they were only a little above 5 mg/l, i.e. in the lower therapeutical range. After 15 d a clinically hardly significant increase in the theophylline clearance was found.