A pharmaceutical active-containing transmucosal delivery device comprises a polymer film comprising a polymer matrix, wherein the film has a pH in the range of about 4 to about 9, and a pharmaceutical active composition disposed on a surface of the polymer film. The composition comprises at least one pharmaceutical active ingredient in the form of particles, and wherein the particles have an average particle size of about 100 nm to about 5 microns, an anti-crystallization agent, and a pH adjusting agent, wherein the concentration of the pharmaceutical active ingredient is at least 20% w/w relative to the total weight of the pharmaceutical active composition. The delivery device exhibits a residence time in the mouth of a subject ranging from about 5 minutes to about 30 minutes and is substantially mucoadhesive to a mucosa surface when placed sublingually under the tongue or placed buccally at the inner lining of the cheek.