Formulation and Evaluation of the Risperidone Solid Dispersion Using Different Carriers
Author(s): Zahraa Kareem Hussein* and Khalid Kadhem Al-Kinani
Abstract
Solid Dispersion (SD) is used in improving drugs’ physicochemical properties including solubility and dissolution and it is considered as a smart method of pharmaceutical technology. The drug risperidone (RIS) is prescribed for the short-term management of acute manic or mixed episodes linked to bipolar disorder, both positive and negative signs, and symptoms of schizophrenia. RIS is class II drug as stated by the Biopharmaceutical Classification System (BCS) which means it has low solubility. In this study, attempts were made to enhance dissolution rate and solubility of RIS by solid- dispersion system. Twenty eight formulas of RIS were prepared as a solid- dispersion using different carriers includes poloxamer 407 (PXM407), polyethylene glycol 6000 (PEG6000), Polyvinylpyrrolidone (PVP K30), and poloxamer188 (PXM188) at different drug: carrier ratios (1:1, 1:2, 1:3, and 1:5) by using two different preparation methods (fusion method and solvent evaporation method). The prepared formulas were characterized for drug content, production yield, solubility study, dissolution study, FTIR, DSC, and PXRD .The results indicate that the used carriers show enhancement in drug solubility in the following rank order: PVP K30>PEG 6000> PXM407> PXM188. The best drug: polymer ratio was 1:5 while best preparation method was solvent evaporation. The optimum formula (drug: PVP K30 at ratio of 1:5) is prepared by solvent evaporation method shows 25-fold enhancement in solubility related to pure RIS. Further characterization of the optimum formula shows amorphousization of RIS. It can be concluded that the solid dispersion can under the selected criteria here can be followed to solve the problem of RIS solubility which could possibly result in better RIS bioavailability.