FORMULATION AND EVALUATION OF FAST DISINTEGRATING RIZATRIPTAN BENZOATE SUBLINGUAL TABLETS

Rizatriptan benzoate is a potent and selective 5-HTIB/ID receptor agonist and is effective for the treatment of acute migraine. Sublingual formulation has the advantage of offering fast relief from migraine due to faster drug delivery. The present study involves the formulation and evaluation of fast disintegrating sublingual tablets of rizatriptan benzoate to produce intended effects. The sublingual rizatriptan benzoate tablets were prepared by the method of direct compression. The superdisintegrants used were sodium starch glycolate, cross carmellose sodium and cross povidone. The powder flow properties of all formulations were evaluated for diameter, thickness, weight variation, hardness, friability, wetting time, water absorption ratio, drug content, in vitro and in vivo disintegration time as well as in vitro release and were found to be satisfactory. The optimised formulation containing cross povidone disintegrated very fast and in vitro drug release was very high. The optimised formulation was characterised by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), powder x-ray diffraction (PXRD) and fourier transform infrared spectroscopy (FTIR). Based on disintegration and dissolution studies, the optimised formulation was also evaluated for in vivo release studies using rabbit model. The peak serum concentration (Cmax), half time needed for item to decay (T½), time for maximum plasma concentration (Tmax) and area under curve (AUC) were calculated. Tmax for rizatriptan tablet was faster in sublingual route when compared to oral route. Rizatriptan tablet by sublingual route in rabbit shows effective therapeutic Cmax when compared to clinical dose and it is a promising alternative to oral administration route in acute management of migraine.