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over rectal diazepam in trials in children, and is now the drug of choice in children and adults.
Recent evidence has indicated that intramuscular midazolam is a superior treatment to
intravenous lorazepam when given by paramedics prior to hospitalisation due to improved
speed of administration and should certainly be considered in all instances in which
intravenous access is difficult.

The earlier treatment is given the better. It is easier to prevent the evolution of epilepsy to
status epilepticus than to treat the established condition. If the patient is at home, AEDs
should be administered before transfer to hospital, or in the casualty department before
transfer to the ward. The acute administration of either diazepam or midazolam will cause
drowsiness or sleep, and rarely cardiorespiratory collapse, and patients should be carefully
supervised.

Early status epilepticus (030 minutes)
Once status epilepticus has developed, treatment should be carried out in hospital, under close
supervision. For the first 30 60 minutes or so of continuous seizures, physiological
mechanisms compensate for the greatly enhanced metabolic activity. This is the stage of early
status epilepticus, and it is usual to administer a fast-acting benzodiazepine.

In most clinical settings, intravenous lorazepam (0.07 mg/kg to a maximum of 4 mg) is the
drug of choice, and this dose can be repeated once if seizure activity does not stop. Other
benzodiazepines such as diazepam, clonazepam and midazolam are alternatives but, due to
its more prolonged action, lorazepam should be preferred. In most patients, therapy will be
highly effective. Continuous 24-hour inpatient observation should follow. In previously non-
epileptic patients, long-term AED therapy should be considered, and in those already on
maintenance antiepileptic therapy, this should be reviewed.

Established status epilepticus (3060/90 minutes)
This can be operationally defined as status epilepticus which has continued for 30 minutes in
spite of early-stage treatment. The time period is chosen because physiological
decompensation will usually have begun. Intensive care facilities are desirable. There are four
alternative treatment options. These are subanaesthetic doses of phenobarbitone (10 mg/kg),
phenytoin (1520 mg/kg), fosphenytoin (a phenytoin pro-drug) or valproate (20–30 mg/kg);
all are given by intravenous loading followed by repeated oral or intravenous
supplementation.

A number of alternative treatment options exist. Although once popular, continuous
benzodiazepine and chlormethiazole infusions on the ward are hazardous and not now
recommended. There have been promising reports of the use of intravenous levetiracetam at
this stage at high doses (2040 mg/kg), but one study has suggested that it may be an inferior
treatment at this stage; randomised controlled studies are presently under way. The new drug
lacosamide is also available as an intravenous preparation but there is limited experience of
this drug at this stage.

Refractory status epilepticus (after 60/90 minutes)
If seizures continue for 6090 minutes after the initiation of therapy, the stage of refractory
status epilepticus is reached and full anaesthesia required. In many emergency situations (for
example, post-operative status epilepticus, severe or complicated convulsive status
epilepticus, patients already in intensive care), anaesthesia can and should be introduced
earlier. Prognosis will now be much poorer, and there is a very high mortality and morbidity.

Anaesthesia can be induced by barbiturate or non-barbiturate drugs. A number of anaesthetics
have been administered, although few have been subjected to formal evaluation and all have
drawbacks. The most commonly used anaesthetics are the intravenous barbiturate