[Epilepsy or functional neurological disorder. Diagnostic strategies].

A seizure is the manifestation of symptoms or signs produced by excessive or synchronous neuronal activity in the brain. It usually presents as brief, self-limited episodes of involuntary movements that can affect a part or the entire body and that are sometimes accompanied by loss of consciousness and sphincter control. Epilepsy may be considered after a single unprovoked seizure in a patient with a high risk of recurrence. Paroxysmal non-epileptic disorders are defined as episodes of sudden onset and short duration that imitate an epileptic seizure, caused by a brain dysfunction of diverse origin that, unlike epilepsy, is not due to excessive neuronal discharge. Its incidence is much higher than epilepsy and it can appear at any age. It is important for diagnosis to analyze the triggering factors, the details of each episode, physical examination and only proceed to basic complementary tests such as video-electroencephalogram in case of doubt or for diagnostic confirmation. There is a tendency to overdiagnose epilepsy and excessive use of anticonvulsant drugs. Those that can most frequently be confused are syncope, "daydreams" and pseudoseizures.