Abstract: Lamotrigine is one of the newer antiepileptic drugs and low aqueous solubility of Lamotrigine is responsible for its poor dissolution and delayed onset of action. The purpose of the present investigation is to increase the dissolution rate of Lamotrigine by preparing its solid dispersions with PEG 6000 using solvent evaporation technique and subjecting them to drug-carrier interaction, dissolution and stability studies and it was found that the dissolution rate was improved for Lamotrigine in its solid dispersion. As indicated from XRD and DSC studies, Lamotrigine was in the amorphous form in the solid dispersions, which confirmed the better dissolution rate of prepared stable solid dispersions. Pharmacokinetic profiles of Lamotrigine and solid dispersion were compared by one way ANOVA followed by Dunnett Post Hoc test which indicated higher attainable plasma concentrations. Solid dispersion showed a difference with the pure drug in its pharmacokinetic profile which may be attributed to better dissolution rate of Lamotrigine from its solid dispersion.
Keywords: Lamotrigine, Solubility, Physical Mixture, Solid dispersions, Solvent evaporation, Pharmacokinetic
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