Combination of lactose (as a carrier) with Cremophor® EL (as a liquid vehicle) to enhance dissolution of griseofulvin

Liquisolid technique is an approach to enhance dissolution of hydrophobic drugs. Most of liquisolid formulations are prepared with microcrystalline cellulose as a carrier which is hydrophobic. Accordingly, this study aimed to replace this hydrophobic carrier with a hydrophilic carrier (lactose) to be used in a combination with Cremophor® EL (as a liquid vehicle which has an inhibitory effect on P-glycoprotein) to improve dissolution of griseofulvin. The effects of carrier to coat ratio (R, ratios used were 10 and 20) and drug concentrations within liquid medications (15 and 20% w/w) on drug dissolution profiles were investigated. The dissolution profiles of liquisolid formulations and pure drug were compared. Solubility measurements, differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR) were used for evaluation of physicochemical properties of griseofulvin in liquisolid powders. Enhanced drug release profiles were obtained due to increased drug solubility, wetting properties and surface area of drug particles available for dissolution. The rate of drug dissolution was significantly enhanced (P < 0.001) from liquisolid formulations compared with pure drug. There were no significance differences (P > 0.05) between formulations prepared with R-value of 10 and 20. The reduction in the drug crystallinity, as indicated by the DSC data, may be the reason for the enhanced drug dissolution from liquisolid powders. The combination of lactose and Cremophor® EL allows the production of liquisolid formulations with low unit dose powder weights.