Inability of the larynx (voice box) to produce normal speech. A person can lose his or her ability to speak when the nerve supply that normally pushes the two vocal cords together is damaged or destroyed. The most common causes of voice loss are viral infections and overuse of the voice. The voice usually returns to normal when the infection clears up or the person uses his or her voice less. Nerve loss can be caused by a stroke, throat cancer or its treatments, or an injury to the throat or neck. Usually, when it becomes impossible to speak, breathing is also restricted, and there is a risk of choking when swallowing. When the loss of voice is severe and prolonged, surgery may be required.
Impaired ability to speak in a normal manner often arises temporarily due to overuse of the voice, leading to strained laryngeal muscles, or from inflammation of the vocal cords as seen in laryngitis.
Chronic or repeated voice loss could be due to factors like polyps on the vocal cords, thickening of the cords from hypothyroidism (low thyroid activity), or disruption of nerve signals to the larynx muscles because of cancers affecting the larynx, thyroid gland, or esophagus. Complete loss of voice is uncommon and is often rooted in psychological factors.