Acne dermatoses (rosacea, perioral dermatitis, seborrheic dermatitis etc.) are one of the most actual problems in dermatology. Praziquantel is an antiparasitic medication effective towards trematodes, cestodes. Investigations developed by domestic scientists revealed antidemodicosis activity of praziquantel. Use of semisolid dosage forms for rectal administration will allow to increase its efficacy and minimize the risks of adverse reactions. The aim of this work is the study of influence of excipients (bases and surfactants) use in suppository manufacturing on the biopharmaceutical characteristics of praziquantel rectal dosage form. Methods and results. As excipients for praziquantel rectal dosage form we have investigated suppository bases and surfactants, which are widely used in manufacturing and compounding of semisolid dosage forms and are described in literature. Suppositories were made by the fusion method. Concentration of surfactants in all compositions was 2%, praziquantel – 0,6 g on one suppository. Investigation was carried out by the 2-factors dispersive analysis with repeated observations. Suppository compounding was carried out by the suspension type. After thorough pulverization of praziquantel, it was mixed with some part of the base and then obtained mixture was added to the all melted base. As optimization parameter the praziquantel releasing was chosen as the first step of bioavailability investigation. Praziquantel releasing from suppository was studied by the equilibrium dialysis by Kruvchinsky. Ethyl alcohol was chosen as a dialysis medium considering the solubility of praziquantel. Concentration of released praziquantel after 30 minutes of the dialysis was determined by spectrophotometric analysis. Conclusion. It has been established that the sort of the base and surfactant have significant influence on praziquantel releasing from rectal suppository. It has been revealed that sort of base has the greatest influence on praziquantel releasing from rectal suppository. Variance analysis has shown optimal praziquantel releasing from rectal suppository with composition of factory fatty base and distilled monoglycerides.