Vestibular Neuronitis

Vestibular neuronitis is a disorder characterized by a sudden severe attack of vertigo (a whirling sensation), caused by inflammation of the nerve to the semicircular canals.

Vestibular neuronitis is probably caused by a virus. It may occur as a single, isolated attack of vertigo lasting several days, although many people have additional attacks of milder vertigo for several weeks thereafter. The first attack of vertigo is usually the most severe. The attack, which is accompanied by nausea and vomiting, lasts for 3 to 7 days. The eyes flicker involuntarily away from the affected side (a sign called nystagmus). Each subsequent attack is shorter and less severe than the previous one, and typically occurs only when the head is in certain positions. Hearing is usually not affected.

Diagnosis involves hearing tests and tests for nystagmus (see Section 6, Chapter 80). Magnetic resonance imaging (MRI) of the head may be performed to make sure the symptoms are not caused by another disorder, such as a tumor.

Treatment of vertigo is the same as in Meniere's disease and consists of drugs such as meclizine, lorazepam, or scopolamine. Nausea and vomiting may be relieved by suppositories containing the drug prochlorperazine. If vomiting continues for a long time, a person may need to be given fluids and electrolytes intravenously. The disorder eventually goes away on its own.