Maria Arini Lopez, PT, DPT, CSCS, CMTPT, CIMT is a freelance medical writer and Doctor of Physical Therapy from Maryland. She has expertise in the therapeutic areas of orthopedics, neurology, chronic pain, gastrointestinal dysfunctions, and rare diseases especially Ehlers Danlos Syndrome.
Dravet syndrome (DS) is a rare type of childhood epileptic encephalopathy characterized by frequent, prolonged seizures that are often refractory to drug treatment. These repeated seizures result in cognitive impairment, developmental delay or regression, motor dysfunction, and behavioral challenges.1 Seizures in DS are often triggered by fever, infections, vaccinations, and elevated body temperature.2
Antiseizure Medication Therapies
Resistance to treatment with antiseizure medications (ASMs) is a common clinical feature of DS. Typically, 2 or more ASMs are required to manage the various seizure types experienced in DS.2
Common antiepileptic medications used to treat DS include Epidiolex® (cannabidiol), Onfi® (clobazam), Diacomit® (stiripentol), Topamax® (topiramate), and Depakote® (valproate).2
The US Food and Drug Administration (FDA) approved 3 pharmacological treatments specifically for patients with DS, including Epidiolex, Diacomit, and Fintepla® (fenfluramine). The FDA approved Fintepla in June 2020 specifically for the treatment of individuals with DS over the age of 2 years.2
Rescue medications, often benzodiazepines, are critical for the management of seizure emergencies in DS. They may be helpful in decreasing seizure duration and preventing life-threatening complications, such as status epilepticus or sudden unexpected death in epilepsy (SUDEP).2,3
Read more about DS therapies
Some individuals with DS may benefit from the ketogenic diet, which has demonstrated an ability to decrease seizure activity in individuals with frequent seizures.2
A study conducted from March 1, 1990 to August 31, 2004 followed 52 individuals with DS for a minimum of 1 year, 20 of whom were placed on the Hopkins protocol ketogenic diet. After 1 year, 13 of the 20 (65%) patients remained on the diet, with 2 (15%) patients achieving complete seizure freedom, 8 (61.7%) patients reporting a 75% to 99% reduction in seizure activity, and 3 (23%) patients experiencing a 50% to 74% reduction in seizure activity. This suggests that the ketogenic diet may be an effective alternative treatment to decrease seizure burden and improve quality of life in those with DS following failure of multiple antiepileptic medications.4
Another study obtained similar results, with 13 of 20 (65%) patients on the ketogenic diet achieving an over 50% reduction in seizures.5
Read more about DS diet and nutrition
Due to the difficulty in managing frequent and prolonged seizures during critical points in childhood development, the majority of children with DS experience worsening developmental delay or regression, motor deficits and orthopedic conditions affecting balance and gait, language delay and dysarthria, behavioral challenges, and cognitive impairment leading to learning disabilities.6 Therefore, children with DS often require and benefit from ongoing physical, occupational, and speech therapy.2
Prior to starting school, children with DS should complete a comprehensive neurodevelopmental examination to determine if these rehabilitative therapies could be helpful in slowing disease progression, maintaining strength and mobility, and improving communication skills.2 Results from this neurodevelopmental examination can be used to formulate an individualized education plan (IEP) for school-aged children with DS.7,8
Read more about the DS care team
Vagus Nerve Stimulation
Vagus nerve stimulation is a surgical procedure that involves electrical stimulation of the left cervical vagus nerve with a helical electrode connected to a pulse generator. Implantation of a vagus nerve stimulation device may reduce seizure activity by more than 50% in some individuals with DS who do not adequately respond to other available treatments for seizure management.6,9
In a long-term study published in 2011, researchers found that over 60% of the 436 patients with treatment-resistant epilepsy who underwent vagus nerve stimulation device implantation demonstrated at least a 50% reduction in seizures.9
Variations in the SCN1A gene result in around 80% of cases of DS; however, SCN1A gene variants may also contribute to the wider clinical spectrum of genetic epilepsy with febrile seizures plus (GEFS+). Research suggests that clinicians must analyze 2 factors when determining if resection might be effective in treating individuals with epilepsy who carry SCN1A variants: the patient’s anatomo-electroclinical phenotype and the pathogenicity of the SCN1A variant.10
Read more about DS genetics
Outcomes are often poor following cortical resection in patients with DS; however, other patients with SCN1A variants causing focal seizures categorized in the GEFS+ spectrum may benefit from focal cortical resection of the affected brain region.10 Given these poor outcomes, epilepsy surgery is not indicated for most individuals with DS.2
Treatments to Avoid
Individuals with DS should avoid the use of sodium channel blockers, including Dilantin® (phenytoin), Lamictal® (lamotrigine), Trileptal® (oxcarbazepine), Banzel® (rufinamide), Tegretol® (carbamazepine), and Cerebyx® (fosphenytoin). These medications may cause increased seizure activity in patients with DS.2
Sabril® (vigabatrin) and Gabatril® (tiagabine) may increase the frequency of myoclonic seizures; therefore, these medications should also be avoided in individuals with DS.2
Read more about DS prognosis
- What is Dravet syndrome? Dravet Syndrome Foundation. Accessed March 17, 2023.
- Joshi C, Wirrell E. Dravet syndrome. Epilepsy Foundation. August 24, 2020. Accessed March 17, 2023.
- Hoerth M, Shafer PO. Seizure rescue therapies. Epilepsy Foundation. April 14, 2019. Accessed March 17, 2023.
- Caraballo RH, Cersósimo RO, Sakr D, Cresta A, Escobal N, Fejerman N. Ketogenic diet in patients with Dravet syndrome. Epilepsia. 2005;46(9):1539-1544. doi:10.1111/j.1528-1167.2005.05705.x
- Laux L, Blackford R. The ketogenic diet in Dravet syndrome. J Child Neurol. 2013;28(8):1041-1044. doi:10.1177/0883073813487599
- Cardenal‐Muñoz E, Auvin S, Villanueva V, et al. Guidance on Dravet syndrome from infant to adult care: road map for treatment planning in Europe. Epilepsia Open. 2022;7(1):11-26. doi:10.1002/epi4.12569
- How to get an individualized education plan (IEP). Neuro Assessment & Development Center. Accessed March 17, 2023.
- Jagadish S, Ganganna ST. Dravet syndrome. Child Neurology Foundation. Accessed March 17, 2023.
- Dibué-Adjei M, Fischer I, Steiger HJ, Kamp MA. Efficacy of adjunctive vagus nerve stimulation in patients with Dravet syndrome: a meta-analysis of 68 patients. Seizure. 2017;50:147-152. doi:10.1016/j.seizure.2017.06.007
- Vezyroglou A, Varadkar S, Bast T, et al; Epilepsy Surgery in SCN1A Study Group. Focal epilepsy in SCN1A-mutation carrying patients: is there a role for epilepsy surgery? Dev Med Child Neurol. 2020;62(11):1331-1335. doi:10.1111/dmcn.14588
Reviewed by Debjyoti Talukdar, MD, on 3/22/2023.