Preformulation experiences and in vitro model studies with spironolactone-containing suppositories

The optimal suppository base for the formulation of rectal suppositories co ntaining diuretic spironolactone was selected experimentally. Model studies were carried out about the effect of solubility-increasing additives on th e release of the drug from the suppositories. During the ill vitro examinat ions acceptor phases of different pH values were used, and both diffusion t ime and the number of samplings were changed. Among the lipophilic and hydr ophilic suppository bases studied the hydrophilic Macrogolum 1540 was found to be optimal. The release and diffusion of spironolactone was the most fa vourable from these suppositories. During storage these suppositories remai ned stable and the values of release did not decrease significantly (p < 0. 05).