Shortness of breath, a 'wearing-off' symptom in Parkinson's disease.

Although levodopa is considered the gold standard for Parkinson's disease therapy, prolonged use of this drug can result in motor complications such as a 'wearing-off' phenomenon. This outcome is seen in a significant number of patients with Parkinson's disease taking levodopa and, in some cases, is observed only a few hours after intake of the last dose of levodopa. Patients experiencing the wearing-off period may present with sensory, autonomic, psychiatric and motor fluctuations. Although infrequent, shortness of breath is an important non-motor wearing-off symptom experienced by patients with Parkinson's disease. In addition to being a symptom induced by wearing off, other causes of shortness of breath include pulmonary diseases, coronary artery disease and anxiety. Thus, it is important to identify the cause of shortness of breath to ensure that the appropriate treatment is initiated. We report here on a patient with Parkinson's disease who was taking levodopa and developed both shortness of breath and hyperventilation during wearing-off periods. He underwent extensive pulmonary and cardiac investigations that were unremarkable. His shortness of breath was determined to be a wearing-off phenomenon and his condition improved with the addition of a catechol-O-methyltransferase inhibitor (entacapone).