Sudden deafness (hereafter referred to as sudden deafness) is a sudden onset of sensory-neural deafness of unknown cause, also known as violent deafness. Its onset is rapid, its progression is rapid, and the outcome of treatment is directly related to the time of consultation, so it should be considered an otologic emergency. Sudden deafness is a type of sensorineural deafness that occurs suddenly and for unknown reasons. Acute vascular obstruction and viral infections are currently thought to be the common causes of this disease. The lesion may involve the spiral apparatus, or even rupture the vestibular membrane or cochlear window membrane. The deafness may appear instantaneously or may peak rapidly within hours or days, mostly unilaterally, but also in both ears, with tinnitus and, in some cases, vertigo. Early treatment can lead to better results. Sudden deafness is often associated with unilateral hearing loss, tinnitus, ear blockage, vertigo, nausea and vomiting.