Influence of Different Concentrations of Surfactants on Dissolution Profiles of Extemporaneously Compounded Pessaries with Clindamycin Phosphate

Three groups of pessaries with clindamycin phosphate as the active substance, and with different concentrations of polysorbate 80 as a surfactant incorporated in the glycerol-gelatin base, were prepared simultaneously. Potential differences in their dissolution profiles and bioavailability were examined, i.e., the influence of surfactant on the release of the active substance. Taking into account the difference and similarity factors, there were little differences in dissolution rates among the tested groups of pessaries with different surfactant concentrations. Therefore, although the surfactant may help to release the drug, it should be used in the appropriate concentration. The prepared pessaries were also tested for uniformity of mass and active substance content. The results showed that the tested pessaries met the pharmacopoeial requirements. This paper focuses on extemporaneously compounded pessaries, because extemporaneously compounded drugs are preparations mostly used for personalized therapy or during drug deficits. However, there are few regulations concerning this type of drug and the content of active substance in them is not monitored. The dissolution test is a method that could potentially be used for auditing extemporaneously compounded pessaries. KEYWORDS: Clindamycin phosphate, pessaries, extemporaneous compounding, dissolution test