Benign paroxysmal positional vertigo (BPPV) is a disorder arising from a problem in the inner ear. Symptoms are repeated, brief periods of vertigo with movement, characterized by a spinning sensation upon changes in the position of the head. This can occur with turning in bed or changing position. Each episode of vertigo typically lasts less than one minute. Nausea is commonly associated. BPPV is one of the most common causes of vertigo. BPPV is a type of balance disorder along with labyrinthitis and Ménière's disease. It can result from a head injury or simply occur among those who are older. Often, a specific cause is not identified. When found, the underlying mechanism typically involves a small calcified otolith moving around loose in the inner ear. Diagnosis is typically made when the Dix–Hallpike test results in nystagmus (a specific movement pattern of the eyes) and other possible causes have been ruled out. In typical cases, medical imaging is not needed. BPPV is easily treated with a number of simple movements such as the Epley maneuver or Half Somersault Maneuver (in case of diagonal/rotational nystagmus), the Lempert maneuver (in case of horizontal nystagmus), the deep head hanging maneuver (in case of vertical nystagmus) or sometimes the less effective Brandt–Daroff exercises. Medications, including antihistamines such as meclizine, may be used to help with nausea. There is tentative evidence that betahistine may help with vertigo, but its use is not generally needed. BPPV is not a serious medical condition, but may present serious risks of injury through falling or other spatial disorientation-induced accidents. When untreated, it might resolve in days to months; however, it may recur in some people. One can needlessly suffer from BPPV for years despite there being a simple an very effective cure. Short-term self-resolution of BPPV is unlikely because the effective cure maneuvers induce strong vertigo which the patient will naturally resist and not accidentally perform. The first medical description of the condition occurred in 1921 by Róbert Bárány. Approximately 2.4% of people are affected at some point in time. Among those who live until their 80s, 10% have been affected. BPPV affects females twice as often as males. Onset is typically in people between the ages of 50 and 70. Signs and symptoms Symptoms: Paroxysmal—appears suddenly, and in episodes of short duration: lasts only seconds to minutes Positional—is induced by a change in position, even slight Vertigo—a spinning dizziness,