IMPROVEMENT OF SOLUBILITY AND DISSOLUTION RATE OF MEFENAMIC ACID BY SOLID DISPERSIONS IN PEG4000

The aim of this study was to prepare and cha racterize solid dispersions of water insoluble non - steroidal anti - inflammatory drug, mefenamic acid ( MA ), with polyethylene glycol 4000 (PEG4000) for enhancing the dissolution rate of the drug. The solid dispersions (SDs) were prepared by hot melting metho d at 1:1, 1:2 and 1:4 drug to polymer ratios. Scanning electron microscopy (SEM), X - ray powder diffractometry (XRD) and differential scanning calorimeter (DSC) were used to examine the physical state of the drug. Further more, the solubility and the dissolu tion rate of the drug in its different systems were explored. The data from the XRD showed that the drug was disappeared in case of higher ratio of IND – PEG4000. DSC thermograms showed the significant change in melting peak of the IND when prepared as SDs s uggesting the change in crystallinity of MA . The highest ratio of the polymer (1:4) enhanced the drug solubility about 4 folds in case of SDs of MA – PEG 4000 . An increased dissolution rate of MA at pH 7.4 was observed when the drug was dispersed in these ca rriers in form of physical mixtures (PMs) or SDs. IND released faster from the SDs than from the pure crystalline drug or the PMs. The dissolution rate of MA from its PMs or SDs increased with an increasing amount of polymer.