A method of treating hypoptyalism in a subject is provided. The method includes administering to the subject a pharmaceutical composition that includes pilocarpine and a bioadhesive polymer. The composition dissolves sublingually in the mouth of the subject and adheres to mucous tissues in the buccopharyngeal cavity. The pilocarpine then dissolves and binds to muscarine receptors present in cells of the subject's salivary glands, endobuccal submucous glands and submaxillary glands, is then absorbed by the cells thereby stimulating the glands to produce saliva.