Acute symptomatic seizures

Acute symptomatic seizures are caused by a transient systemic or central nervous system insult (see examples of causes). For seizures caused by a known toxin or drug, see specific treatment in the Toxicology and toxinology guideline. If alcohol withdrawal cannot be excluded as the cause of a seizure, give intravenous thiamine (see advice for Wernicke encephalopathy).

Resolution of the cause usually stops the seizure. Seizures will recur if the cause recurs (eg during benzodiazepine withdrawal) or if the acute illness has caused permanent brain injury (eg gliosis caused by herpes encephalitis). Acute symptomatic seizures may take the form of status epilepticus—if the seizure continues after 5 minutes, treat as for status epilepticus.

If the cause of an acute symptomatic seizure has been corrected and it is unlikely that the patient will have recurrent seizures (eg when the seizure was caused by hyponatraemia), continued antiepileptic drug therapy is not needed. However, sometimes continued antiepileptic therapy is needed to prevent recurrent seizures when the cause is not immediately reversible (eg bacterial meningitis, eclampsia). In these patients, consider withdrawal of antiepileptic therapy when a minimum of 3 months has elapsed without further seizure activity.