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Dravet syndrome


ICD-10: G40.4

ORPHA: 33069

General information

Estimated occurrence
3-5:100,000 live births. More common in boys.
Genetic, often a change to chromosome 2 (2q24.1). Heredity is autosomal dominant, but in most cases, the disease is caused by a de novo mutation.
General symptoms
Epileptic seizures appear during the first year of life. The children suffer from repeated clonic or tonic-clonic protracted seizures triggered by fever, and affecting consciousness. As time goes by, the seizures become more easily triggered (not just triggered by fever), and can occur so close together that the child doesn’t regain consciousness between seizures. Different types of seizures may also emerge. From around the age of two, the children develop symptoms like developmental disabilities, motor skill difficulties, hyperactivity, communication difficulties and behavioural abnormalities. Other common symptoms are sleep disorders, infection susceptibility, affected growth, and forward-leaning, stiff walking. The condition improves and stabilises from age four or five.
Severe myoclonic epilepsy of infancy, SMEI

Orofacial/odontological symptoms

Children suffering from Dravet syndrome can get their teeth slightly late, and a small number of children experience dental development disruptions, which results in teeth of smaller size and different shape. Teeth grinding is common. The epileptic seizures increase the risk of dental injury. Many take medicines that can have side effects such as dry mouth, heartburn, vomiting and increased bleeding tendency. Oral motor skills can be affected, resulting in difficulties eating and speaking, and reduced saliva control.

Advice on follow-up and treatment

  • Early contact with dental services for intensified prophylactic care and oral hygiene information is essential.>/LI>
  • Tooth grinding should be followed up, and be managed with a splint when necessary.
  • When treating medically compromised patients always contact their doctor for medical advice (bleeding problems, heart diseases etc).
  • Speech, language and communication training are often required.
  • Feeding and swallowing difficulties are investigated and treated by a specialist team at the hospital or multidisciplinary treatment centre.
  • Training in oral motor skills and extra stimulation in cases of eating disorders, speech difficulties and impaired saliva control may be necessary.


Updated: 2019-11-12 14:35