Effect of combination of some Polymers with Carbopol 940 on Pregabalin Release Rate from Emulgels

Topical Emulgels of Pregabalin were formulated using Carbopol 940 in combination with (PVP k90, PEG 200, PEG 1000, HPMC K15M) to obtain the optimal formula in terms of drug release rate. Physical appearance, pH, viscosity, stability, drug content, In-vitro drug release, Differential scanning calorimetry and Fourier transform infrared spectroscopy, were tested in all formulas and evaluated to determine the best one. All formulations had good physical properties and stability, F2 which contains Carbopol 940 0.4% and HPMC K15M 0.4% gave the best drug release rate: (30% in 20 min and 93% in 360 min). But F3 which contains Carbopol 940 0.4% and PEG 200 10% showed the less release rate at 360 min: (64%). F2 showed Korsmeyer–Peppas model Kinetic release. So F2 was the best formula because it released drug since 10 min and still to 360 min (6 hours), thus F2 can be used to obtain rapid analgesic effect and avoid CNS-mediated side effects of Pregabalin.