Development of buccal tablets for curcumin using Anacardium occidentale gum

The objective of the present investigation was to develop unidirectional, bilayered, buccoadhesive tablets of curcumin using a natural buccoadhesive polymer cashew nut tree gum along with ethyl cellulose as an impermeable backing layer. A batch prepared with 20% polymer concentration, 0.1% penetration enhancer, 40 mg backing layer, compressed at 2 tons/cm2 for 10 s was identified as an ideal batch based on its buccal residence time and optimum mucoadhesive strength of 13.99 g. The formulated tablets were stable with respect to their physicochemical and in vitro drug release behaviour over a period of 60 days at different temperatures and relative humidities. The kinetics of drug release was found to be non-Fickian or anomalous diffusion. The results suggest that cashewnut tree gum can be used as a polymer to produce buccoadhesive tablets of curcumin with potential to bypass the first pass metabolism and improve the bioavailability of curcumin.