Disorders of taste.

At least 2 million Americans suffer with chemosensory dysfunction or disorders of taste and smell. In addition to the obvious aesthetic deprivation, loss of taste may affect an individual's health and psychosocial situation. Most taste disorders are associated with antecedent upper respiratory infection, trauma, or allergic rhinitis, or have an idiopathic etiology. They may reflect underlying neoplastic, neurologic, endocrine, infectious, or nutritional disturbances; only 1% of these patients have a functional disorder. Evaluation consists of a history and physical, followed by a screening test battery searching for any of the treatable etiologies. One third of patients will respond to exogenous zinc therapy after a treatment period of 2 to 4 months. The remainder must rely on supportive measures such as additives, flavor enhancers, and rinses.