Differential diagnosis of epileptic seizures

This includes:
Awake episodes

Normal phenomena	déjà vu may be normal
Behavioural phenomena	particularly in people with a learning disability
Paralytic syncope	due to impaired autonomic function eg drug effects, autonomic neuropathy
Cardiac arrhythmias	especially in middle and older age but can occur in the young, may have prodromal palpitations, pallor is common
Other cardiac disorders	can sometimes produce focal neurological features from low output
Panic attacks	fear anxiety, light-headedness, peripheral paraesthesiae, often in anxiety inducing situations
Concussive seizures	occurring immediately after a concussive closed head injury, no risk of recurrence
Hypoglycaemia	almost always in diabetes or alcoholics after a binge, causing stupor, confusion, bizarre behaviour, tremulousness, occasionally seizures
Transient ischaemic attack (TIA)	usually older patients, needs to be differentiated from simple partial seizures
Paroxysmal movement disorders	very rare, presents with sudden choreoathetosis or dystonia, may be triggered by movement, could be mistaken for partial motor seizures
Tonic spasm of multiple sclerosis (MS)	with intense focal spasm for less than a minute or longer, in patients with established MS
Tics	multiple tics could be confused with myoclonic jerks, but in the most important disorder, Gilles de la Tourette Syndrome, there is also an obsessive compulsive behaviour with accompanying vocalisations
Idiopathic drop attacks	occurs in middle-aged females, with sudden devastating falls without loss of consciousness, and therefore differs from the presentation of atonic seizures in children and young adults
Migrainous aura	a march of less than a minute suggests partial seizures; over several minutes suggests migraine
Transient global amnesia	usually >40 years of age, with amnesia lasting from 30 minutes to a few hours

Sleep related episodes

Hypnic jerks	on falling asleep
Sleep paralysis	frightening episodes of paralysis of voluntary movement on awakening or falling asleep
Exploding head syndrome	sensation of exploding on falling asleep
Periodic movements of sleep	older patient, flexion of leg for a few seconds, at intervals of 10-60 seconds occurring in clusters for several minutes
Non REM parasomnias	sleep walking, sleep talking
REM parasomnias	often violent behaviours, may be related to dream content
Sleep apnoea	snoring, apnoeic episodes, daytime drowsiness

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