Patent attributes
The present invention provides an oral transmucosal film or patch for delivering doxepin through the buccal mucosa or sublingual mucosa. The film or patch is a bilayer structure containing a mucoadhesive layer with amorphous doxepin and soluble backing layer without doxepin. The film or patch has satisfactory bioavailability and improved palatability. The mucoadhesive layer comprises 0.5-25% (w/w) of doxepin, 50-96% of one or more film-forming agents, 1-30% (w/w) of one or more adhesives, and 0.05-5% (w/v) of one or more stabilizers. The backing layer comprises 80-100% (w/w) of one or more film-forming agents. Preferred adhesives include povidone, carbomer, and polycarbophil. Preferred stabilizers include butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), citric acid, and ascorbic acid.