Laryngeal tardive dyskinesia

Neuroleptic treatment frequently induces movement disorders, the tardive dyskinesias. These are frequently seen in the orobuccolingual region. Although the beginning of neuroleptic treatment can cause acute dystonia and breathing difficulty, chronic neuroleptic treatment has only rarely been shown to affect the laryngeal musculature. Laryngeal abnormal movements were assessed in 12 patients receiving chronic neuroleptic treatment who showed orobuccolingual abnormal movements. The Abnormal Involuntary Movement Scale was systematically assessed in all patients. Clinical examination revealed that 8 had speech disorders, 8 had breathing difficulties, and 5 had swallowing disorders. Laryngeal endoscopy showed that 10 of the patients had intermittent partial obstruction of the glottis, due to repetitive abnormal adduction of the vocal cords. Percutaneous electromyography of the thyroarytenoid muscles showed spontaneous irregular and prolonged muscular contractions, while the patients were at rest and when speaking. The patients were not aware of these movements. In view of this finding, laryngeal dyskinesia should be considered and studied as a possible side-effect of chronic neuroleptic use.