Dravet syndrome, also called severe myoclonic epilepsy of infancy (SMEI), is a severe form of epilepsy. It appears during the first year of life with frequent febrile seizures – fever-related seizures that, by definition, are rare beyond age 5. Later, other types of seizures typically arise, including myoclonus (involuntary muscle spasms). Status epilepticus – a state of continuous seizure requiring emergency medical care – also may occur. Children with Dravet syndrome typically experience poor development of language and motor skills, hyperactivity, and difficulty relating to others.

Seizures in Dravet syndrome are difficult to control, but can be reduced by anticonvulsant drugs. A ketogenic diet, high in fats and low in carbohydrates, also may be beneficial.

As children with Dravet syndrome get older, their decline in cognitive function stabilizes, and in many, it improves slightly. However, most teenagers with Dravet syndrome are dependent on caregivers. The degree of cognitive impairment appears to correlate with the frequency of seizures.

Prepared by the National Institutes of Health