Introduction

This review presents a comprehensive approach to children and adults with a first seizure, an event that may have profound emotional, social, and vocational consequences.

A first “grand mal” convulsion is frightening, yet prospective, population-based studies indicate that we all face an 8-10% lifetime risk of one seizure1 and a 3% chance of epilepsy.2 It seems likely that everyone could have a seizure if a particular set of circumstances occur—but some people have a lower seizure threshold than others. A first seizure caused by an acute disturbance of brain function (acute symptomatic or provoked) is unlikely to recur (3-10%). If a first seizure is unprovoked, however, meta-analyses suggest that 30-50% will recur; and after a second unprovoked seizure, 70-80% will recur, justifying the diagnosis of epilepsy (a tendency for recurrent seizures).3^–5

When a person presents to the healthcare system with a first seizure, it is almost always a convulsive seizure, either generalised or focal. Other seizure types such as absence or complex partial seizures typically occur several times before the person or family become concerned.

Methods

We reviewed all literature listed in PubMed under the headings “first seizure” and “initial seizure.” Two of us have helped to develop a practice parameter on treatment of a first seizure in children, and all of us have conducted prospective studies of first seizures. We are unaware of any systematic (Cochrane) review of this topic. All references cited were judged to give strong evidence.

Is it a seizure?

The differential diagnosis for a first seizure is wide. Most important in our experience are syncope (including breath holding and pallid syncope), transient ischaemic attacks, metabolic encephalopathy (including hypoglycaemia or electrolyte disturbance), sleep walking, night terrors, complex migraines, cardiac arrhythmias, and pseudoseizures. “Convulsive syncope” presents a particular challenge when syncope provokes a post-anoxic convulsion. A detailed …