FORMULATION AND CHARACTERIZATION OF GRANISETRON SUBLINGUAL BUCCAL FILMS USING DIFFERENT POLYMERS AND PLASTICIZERS

Background: Granisetron hydrochloride (Granisetron HCl)is a potent 5-HT₃ receptor antagonist used for the preventionof chemotherapy-induced nausea and vomiting. However, itsextensive hepatic first-pass metabolism and delayed onsetfrom oral dosage forms limit therapeutic efficiency.Sublingual buccal films offer a promising alternative forrapid systemic absorption and improved patient compliance.Methods: Granisetron HCl films were prepared by thesolvent-casting method using different film-formingpolymers hydroxypropyl methylcellulose (HPMC K4M),polyvinyl alcohol (PVA), and gelatin in various ratios.Propylene glycol was employed as a plasticizer, and citric acidanhydrous as a saliva-stimulating agent. The prepared films(F1–F5) were evaluated for physicochemical parameters,drug content, mechanical properties, surface pH, in- vitrodisintegration, and dissolution behavior. Drug–excipientcompatibility was examined using FTIR and DSC analyses.Results: All formulations exhibited smooth surfaces,uniform weight (49.5–55.8 mg), and adequate flexibility (folding endurance > 230). Thesurface pH (6.3–6.7) was within the physiological range of the buccal cavity, indicatingmucosal safety. The disintegration time ranged from 9 to 14 seconds, with formulationF5 showing the fastest disintegration and highest cumulative drug release (98.34 %)within 25 minutes in phosphate buffer (pH 6.8). FTIR and DSC studies confirmed the absence of drug–excipient interactions and the thermal stability of the optimizedformulation. Conclusion: The study demonstrates that sublingual buccal films ofGranisetron HCl can be effectively formulated using HPMC and PVA with propyleneglycol as plasticizer to achieve rapid disintegration and enhanced dissolution. The optimizedformulation (F5) offers a patient-friendly, non-invasive dosage form with potential forrapid onset of action in the management of chemotherapy-induced nausea and vomiting.