[Experiences with the rectal use of chemotherapeutic agents. 2. Pharmacokinetic examinations with animals].

The aim of the investigations was to optimise vehicle for trimethoprim (TMP) suppositories ready for clinical trials. The rectal absorption of TMP was studied in anaesthetized rats. The drug liberation properties of the five mixed vehicles with promising in vitro results (Part 1.

[Experiences with the rectal use of a chemotherapeutic agent. 1. In vitro biopharmaceutical examinations; selection of the optimal vehicle].

The factors influencing in vitro liberation (Part 1) and in vivo absorption (Part 2) from trimethoprim-containing rectal suppositories and the authors' results related to them are reported in this two-part publication. Special emphasis was laid on selecting the optimal suppository base which is harmless physiologically yet not indifferent pharmacologically. From among the 24 compositions studied, a lipophilic mixture containing a surface active additive (Witepsol W 35) and a hydrophilic (Macrogolum) mixture were found to be the best in all respects.

Experiences with the rectal use of trimethoprim.

The possibility of rectal use of trimethoprim was studied. The in-vitro liberation of the drug from 24 different suppository bases was examined and the results used to select bases for in-vivo examination. The in-vitro liberation from the suppositories containing 50-200 mg trimethoprim was studied by the method of dynamic diffusion, and the released drug content was measured spectrophotometrically.