Thermal and non-thermal methods to evaluate compatibility of granisetron hydrochloride with tablet excipients

Compatibility of granisetron hydrochloride with selected excipients was assessed using Differential Scanning Calorimetry (DSC) as a thermal screening technique. Non-thermal methods like Fourier Transform Infrared spectroscopy and Thin Layer Chromatography were used as complementary techniques to adequately support and assist in interpretation of DSC results. Some drug-excipient interaction was observed with beta-cyclodextrin, 2-hydroxypropyl-beta-cyclodextrin, mannitol, and magnesium stearate in DSC studies. However, further evaluation of these incompatible excipients with non-thermal methods showed that these excipients were compatible with granisetron hydrochloride. Non-thermal methods were, thus, of help in interpreting DSC results and excluding all relevant pharmaceutical incompatibilities.