Drop attacks: a practical guide

'Drop attacks' encompass both falls and transient loss of consciousness, but the term is not clearly defined. We offer our definition and explore the differential diagnoses. The most common causes are cardiovascular. We discuss clinical and electrographic criteria that suggest underlying arrhythmia or other serious cardiac disorders that require further investigation, and the potential diagnoses that may underlie these 'worrying syncopes'. Vestibular dysfunction also commonly causes collapses, sometimes without typical vertigo. These two common conditions may coexist especially in the elderly. Falls in elderly people often require assessment through a lens of frailty and multifactorial risk factors, rather than seeking a unitary diagnosis. Some drop attacks may be due to longstanding epilepsy and we discuss how to approach these cases. Functional neurological disorder is a common cause in younger people, for which there may also be clinical clues. We review the rarer causes of collapse that may be described as drop attacks, including cataplexy and hydrocephalic attacks.