Development of lamotrigine solid dispersion for the formulation and evaluation of fast dissolving tablets

Lamotrigine is an anticonvulsant drug used in the treatment of epilepsy and bipolar disorders. Its acts primarily by obstructing voltage dependent sodium channel hence a decreased level of excitatory neurotransmitter. Solid dispersion is a newer technique of enhancing the solubility of poorly soluble drugs using suitable polymer. Moreover, for obtaining better drug absorption, faster onset of action and safety regarding its administration fast dissolving tablets are becoming standards. These upon administration into mouth gets rapidly dissolve due to presence of saliva without any need of water. Lamotrigine solid dispersion was prepared using PEG 6000 as polymer in the ratio (1: 1). Fast dissolving tablet of lamotrigine was formulated using 3 different superdisintegrants (crosscarmellose, kollidon, sodium starch glycolate (SSG)) in different ratios. The formulated tablets were then evaluated for its different parameters. The result of invitro dissolution study showed that formulation F5 is most successful as it dissolved in a very short period containing combination of kollidon and SSG in the ratio (1: 3). An increased disintegration time was noted with combination of crosscarmellose and SSG (1: 1) ratio.