Spasmodic dysphonia is a disorder characterized by involuntary movements of one or more muscles of the larynx or voice box. The first signs of spasmodic dysphonia are most often found in individuals between 30 and 50 years old.

More women appear to be affected by spasmodic dysphonia than men. With spasmodic dysphonia, movement of the vocal cords is forced and strained resulting in a jerky, quivery, hoarse, tight or groaning voice.

At present, there is no cure for spasmodic dysphonia. However, several treatment options do exist for voice improvement. Repeat injections of small doses of botulinum toxin (Botox) into one or both vocal cords are frequently recommended. Botox weakens the laryngeal muscles and results in a smoother, less effortful voice because of less forceful closing of the vocal cords. Temporary breathiness or difficulty swallowing sometimes occurs for a short time after injection. Treatment by a speech-language therapist may also be recommended following injections to optimize voice production.