Although exact definitions vary, the term status epilepticus generally refers to the occurrence of a single unremitting seizure with a duration longer than 5 to 10 minutes or frequent clinical seizures without an interictal return to the baseline clinical state [1-3].
The diagnostic evaluation and clinical management of status epilepticus will be discussed here. The management of chronic epilepsy, the actions of antiepileptic drugs, and the management of status epilepticus in children are discussed separately. (See "Overview of the management of epilepsy in adults" and "Pharmacology of antiepileptic drugs" and "Management of status epilepticus in children".)
It is estimated that there are 100,000 to 200,000 episodes of status epilepticus in the United States annually .
Refractory status epilepticus, defined as ongoing seizures following first- and second-line drug therapy, was noted in nearly 30  to 43  percent of patients with status epilepticus. Although not associated with increased mortality, refractory status epilepticus was linked to prolonged hospitalization and poorer functional outcomes. Encephalitis was associated significantly more often with refractory than with nonrefractory status epilepticus (22 versus 4 percent, respectively). In contrast, inadequate serum levels of antiepileptic drugs (AEDs) were associated significantly more often with nonrefractory than with refractory status epilepticus (28 versus 0 percent, respectively). Also, generalized tonic-clonic status was less likely to be refractory than nonconvulsive or focal motor status.
Optimal management of status epilepticus requires identification and correction, if possible, of any predisposing factors that are present. Virtually any acute or chronic brain injury, as well as a number of toxic-metabolic insults, can cause status epilepticus [1,7]. Some of the more common predisposing factors include: