Design, Formulation and Evaluation of an Oral Gel from Punica Granatum Flower Extract for the Treatment of Recurrent Aphthous Stomatitis

Purpose: Recurrent aphthous stomatitis is a disease with unknown etiology that’s mostly treated symptomatically and has no definite cure. Pomegranate (Punica granatum) flowers have been used as medicinal herb that due to its antimicrobial, antioxidant, anti-inflammatory, analgesic and healing effects, has been useful in treatment of oral aphthous. Therefore, we decided to formulate a mucoadhesive gel with pomegranate flower extract to reduce the need for corticosteroid therapy in patients. Methods: Pomegranate flowers are extracted by percolation method. Several formulations with different amounts of carbomer 934, sodium carboxymethylcellulose (SCMC) and hydroxypropyl methylcellulose K4M were prepared and the condensed extract was dispersed in polyethyleneglycol (PEG) 400 and added to gel bases. Then the formulations underwent macroscopic and microscopic studies. The formulations that passed these tests successfully were studied through assay tests using spectrophotometry in 765 nm, drug release from mucoadhesive gel using cell diffusion method, viscosity test, mucoadhesion test and accelerated stability test. Results: The phenolic content of pomegranate flower dried extract was found to be 212.3±1.4 mg/g in dried extract. The F4–F6 formulations contains carbomer 934, SCMC, pomegranate flower extract, PEG 400, potassium sorbate and purified water passed all above tests. Conclusion: The F4 formulation had higher viscosity and mucoadhesion values due to its higher carbomer 934 and SCMC content. Since F4, F5 and F6 had no significant variation in drug release, the F4 formulation was chosen as the superior formulation because of proper appearance and uniformity, acceptable viscosity, mucoadhesion and stability in different temperatures.