Diagnosis guide for clinicians
Dravet syndrome: when to suspect it and what to test
Dravet syndrome is an infantile onset developmental and epileptic encephalopathy, and nearly all cases come from pathogenic SCN1A variants causing Nav1.1 haploinsufficiency.Source 2022 international consensus
ILAE describes a typical first-year presentation in a developmentally normal child with prolonged febrile and afebrile hemiclonic or generalized tonic-clonic seizures.
Source ILAE diagnostic manualA Biocodex-supported European survey found a median of 11 months from seizure onset to diagnosis, with late referral and slow genetic testing driving delays.
Source DS'coverED European survey- Inheritance
- Autosomal dominant
- Age of onset
- Neonatal, Infancy
- Prevalence
- 1 to 9 per 100,000 prevalence at birth, Europe
- Also called
- SMEI, Severe myoclonic epilepsy of infancy, Severe myoclonus epilepsy of infancy
Live from Orphanet (INSERM) via Orphadata, licensed CC BY 4.0, data version 2026-06-23.
Patterns that should prompt a test for Dravet syndrome
Each sign below is common on its own, which is why Dravet syndrome is missed. Published studies describe these combinations as the picture to act on. Rows are ordered from the highest published figure to the lowest, within each kind of measure.
Where testing finds it
Share of each screened or biopsied group found to have Dravet syndrome, from the cited studies. A bar spans the lowest to the highest published figure.
- 1
SCN1A pathogenic variant+First seizure before age 6 months
SCN1A variant carriers with seizures, from an Italian cohort of 182 carriers ascertained after seizure onset
Dravet syndrome followed in 85% of carriers with onset before 6 months, 51% at 6 to 12 months and none after 12 months (Cetica 2017).Cetica 2017 SCN1A carrier study
- 2
Encephalopathy with refractory seizures+First seizure within 72 hours of a vaccination+Previously labeled vaccine encephalopathy
Patients, 14 in all, with alleged vaccine encephalopathy whose first seizure came within 72 hours of vaccination
SCN1A variants were found in 11 of 14, or 78.6%, including all 8 with the severe myoclonic epilepsy phenotype (Berkovic 2006).Berkovic 2006 vaccine encephalopathy study
- 3
First febrile seizure soon after a vaccination+Generalized tonic-clonic seizure lasting over 15 minutes
Australian children with a first febrile seizure, 69 vaccine-proximate and 75 not, sequenced for SCN1A
Pathogenic SCN1A variants were found in 2 of 69 vaccine-proximate cases, both later Dravet syndrome, and 1 of 75 others (Damiano 2020).Damiano 2020 vaccine febrile seizure study
- 4
Seizure reported after a first-year vaccination+Seizure with a temperature below 38.5°C+Seizures recurring after later vaccinations
Dutch children, 1269 in all, reported to national vaccine safety surveillance with seizures after vaccination, 1997 to 2006
Of reported seizures after first-year vaccinations, 2.5% were due to SCN1A Dravet syndrome, and 1.2% across the first 2 years (Verbeek 2013).Verbeek 2013 Dutch vaccination cohort
How often diagnosed patients show it
Share of patients already diagnosed who had the finding, in the group named on each row. Groups differ by age and type, so read each row with its group.
- 1
Seizures that worsen on lamotrigine+Drug-resistant focal and generalized seizures in childhood
Patients with severe myoclonic epilepsy, the older name for Dravet syndrome, aged 2 to 18 and given lamotrigine
Lamotrigine was followed by seizure worsening in 17 of 21 patients, or 80%, and stopping it brought improvement in 18 (Guerrini 1998).Guerrini 1998 lamotrigine report
Also described, without a comparable figure
- Febrile seizures before age 1 + Onset at 7 months or younger, 5 or more seizures, or seizures over 10 minutes + Hemiconvulsions, myoclonic or hot water-induced seizures: No yield figure was found in the abstract; Hattori's score flags a total of 6 or more as high risk and recommends SCN1A analysis.Hattori 2008 screening score
These figures describe published study groups. They are not the chance that any one patient has Dravet syndrome, and bars whose ranges overlap are not in a settled order.
Red flags for Dravet syndrome
What the cited sources describe, grouped by life stage and organ. Each line links to its source.
First seizures in infancy
- Seizure onset typically falls between 3 and 9 months, with a median of 6 months and a range of 1 to 20 months.ILAE diagnostic manual
- ILAE lists recurrent hemiclonic febrile and afebrile seizures, which often alternate sides from seizure to seizure, as a mandatory feature.ILAE diagnostic criteria
- A first prolonged hemiclonic seizure or convulsive status epilepticus with fever or after vaccination, in a previously normal infant.2022 international consensus
- In a US population cohort, all 8 infants with Dravet syndrome had febrile seizures, and 6 had seizures over 10 minutes by age 1.Wu 2015 US incidence study
- Episodes of status epilepticus are common before age 5 years, according to ILAE's diagnostic manual.ILAE diagnostic manual
Triggers
- Seizures are frequently triggered by fever, heat, illness or immunization, according to ILAE's diagnostic manual.ILAE diagnostic manual
- GeneReviews lists hyperthermia from a hot bath, physical exertion or post-vaccination fever, and light stimuli, as common seizure triggers.GeneReviews
- In 40 children with SCN1A Dravet syndrome, 12 had their first seizure on the day of vaccination or the day after.McIntosh 2010 vaccination study
- In Dutch surveillance data, post-vaccination seizures in Dravet syndrome more often occurred with a body temperature below 38.5°C, at 57.9% versus 32.6%.Verbeek 2013 Dutch vaccination cohort
- The same Dutch study found seizures recurred after later vaccinations in 26.7% of children with Dravet syndrome, against 4.0% without it.Verbeek 2013 Dutch vaccination cohort
Seizure types after the first year
- Myoclonic and atypical absence seizures appear between ages 1 and 4 years, according to ILAE's diagnostic manual.ILAE diagnostic manual
- The consensus panel put myoclonic seizures in 50% to 90% of cases, usually starting between 1 and 3 years.2022 international consensus
- Obtundation status, focal dyscognitive seizures and atypical absences are often seen after age 2 years, per GeneReviews.GeneReviews
- ILAE cautions that tonic seizures and epileptic spasms are not expected and should prompt consideration of other epilepsy syndromes.ILAE diagnostic manual
Development, behavior and gait
- Development is usually normal before 18 months, with subtle delays typically evident between 18 and 36 months, per the consensus.2022 international consensus
- The consensus reports intellectual disability in most children aged 3 years and older, with most young adults moderately to severely affected.2022 international consensus
- Attention problems are present in most school-aged children and teens with Dravet syndrome, according to the consensus panel.2022 international consensus
- GeneReviews describes crouched gait, hypotonia, incoordination and impaired dexterity, typically evident by age 3 to 4 years.GeneReviews
Response to medicines
- GeneReviews lists seizures that worsen on sodium channel inhibitors such as carbamazepine, oxcarbazepine, phenytoin or lamotrigine as a suggestive feature.GeneReviews
- ILAE's diagnostic manual cautions that antiseizure medicines with sodium channel blocking properties may aggravate seizures in Dravet syndrome.ILAE diagnostic manual
- In a UK cohort of 241 patients with SCN1A-positive Dravet syndrome, seizure aggravation was reported with carbamazepine and lamotrigine.Brunklaus 2012 UK cohort
Family history
- Most SCN1A Dravet syndrome results from a de novo variant, so a negative family history is the usual finding.GeneReviews
- GeneReviews presumes a parent carries the SCN1A variant when that parent has other family members who have seizures.GeneReviews
- The phenotype of SCN1A seizure disorders can vary even within the same family, from febrile seizures alone to Dravet syndrome.GeneReviews
Dravet syndrome is often mistaken for
Diagnoses patients commonly carry first, and why the sources say they are confused.
| First diagnosis | Why it is confused |
|---|---|
| Simple or complex febrile seizures | GeneReviews notes febrile seizures may be the first manifestation of an SCN1A variant, and children presenting this way can progress to Dravet syndrome.GeneReviews |
| Genetic epilepsy with febrile seizures plus (GEFS+) | The authors of a European diagnostic survey name phenotypic overlap with GEFS+ as a reason Dravet syndrome is misdiagnosed.DS'coverED European survey |
| Vaccine encephalopathy or vaccine injury | Berkovic and colleagues found SCN1A variants in 11 of 14 children labeled with vaccine encephalopathy, all arising de novo where parents were tested.Berkovic 2006 vaccine encephalopathy study |
| PCDH19 clustering epilepsy | ILAE notes it is limited to females, who have clusters of seizures with fever rather than prolonged febrile status epilepticus.ILAE differential diagnoses |
| Lennox-Gastaut syndrome | GeneReviews notes only a minority with the Lennox-Gastaut phenotype carry SCN1A variants, usually in families where Dravet syndrome occurs.GeneReviews |
| Epilepsy with myoclonic atonic seizures | ILAE lists epilepsy with myoclonic atonic seizures, along with GEFS+ and Lennox-Gastaut syndrome, among the differential diagnoses of Dravet syndrome.ILAE differential diagnoses |
| Acquired encephalopathy, infection or injury | GeneReviews lists trauma, hypoxia, infectious or autoimmune cerebritis and toxins among causes to consider when the family history is negative.GeneReviews |
Codes patients often carry before this diagnosis
For spotting the pattern in a problem list or registry. Descriptions are checked daily against NLM's ICD-10-CM service; this is not coding advice.
R56.01Prolonged or focal febrile seizures in infancy are the classic first presentation the consensus says should prompt genetic testing.2022 international consensus
R56.00GeneReviews notes febrile seizures may be the first manifestation of an SCN1A variant before Dravet syndrome becomes apparent.GeneReviews
T50.A95A, T50.B95A, T50.Z95AIn Dutch surveillance, 2.5% of reported seizures after first-year vaccinations were due to SCN1A Dravet syndrome.Verbeek 2013 Dutch vaccination cohort
R56.9Afebrile prolonged hemiclonic seizures and status epilepticus also fall within the consensus testing criteria for infants aged 2 to 15 months.2022 international consensus
G40.901, G40.909, G40.911, G40.919A European survey found a median of 11 months between seizure onset and a formal diagnosis of Dravet syndrome.DS'coverED European survey
G40.811, G40.812, G40.813, G40.814ILAE lists Lennox-Gastaut syndrome among the differential diagnoses of Dravet syndrome.ILAE differential diagnoses
Testing for Dravet syndrome, step by step
The testing order the cited guidance describes, by who it applies to. It summarizes published guidance and is not a plan for any one patient.
Developmentally normal infants aged 2 to 15 months
- When the consensus says to test
Strong consensus supports genetic testing after a single hemiclonic seizure of 5 to 29 minutes, or status epilepticus of 30 minutes or more. This applies with fever or after vaccination, when no other cause is found.2022 international consensus
- Other single seizures with moderate consensus
The panel reached moderate consensus for a prolonged generalized tonic-clonic seizure at 2 to 5 months with fever or vaccination. It also supported testing after afebrile status epilepticus or a prolonged afebrile hemiclonic seizure.2022 international consensus
- Recurrent seizures
Strong consensus supports testing with recurrent prolonged focal or generalized convulsive seizures, with or without fever. It also covers recurrent brief afebrile hemiclonic seizures at 6 to 15 months.2022 international consensus
- Testing outside that window
The consensus says its criteria do not preclude testing elsewhere. Dravet syndrome can present up to 19 months, with brief afebrile seizures or developmental delay.2022 international consensus
Infants with febrile seizures
- Prolonged febrile seizures by age 1
Wu and colleagues concluded that genetic testing should be considered in children with 2 or more prolonged febrile seizures by 1 year of age.Wu 2015 US incidence study
- A clinical risk score before age 1
Hattori's score weighs onset at 7 months or younger, 5 or more seizures, seizures over 10 minutes, hemiconvulsions and hot water triggers. The authors recommend SCN1A analysis when the total score is 6 or more.Hattori 2008 screening score
- Syndrome in evolution
ILAE says the syndrome should be considered in a child under 12 months with a prolonged febrile hemiclonic or tonic-clonic seizure and no other cause.ILAE diagnostic criteria
Any child with suspected Dravet syndrome
- Exclude other causes
ILAE calls MRI not required for diagnosis but highly recommended to exclude other causes, and lists a structural cause as exclusionary.ILAE diagnostic criteria
- EEG expectations
The consensus says the EEG background is typically normal before 12 months, apart from postictal slowing. Interictal discharges appear in most cases by age 5 years.2022 international consensus
- Epilepsy multigene panel: the consensus view
Provided its cost is similar to SCN1A targeted testing, 90% of consensus physicians called an epilepsy gene panel the preferred study for young children.2022 international consensus
- Epilepsy multigene panel: the GeneReviews view
GeneReviews recommends an epilepsy multigene panel that also includes deletion/duplication analysis, since the phenotype overlaps many other inherited seizure disorders.GeneReviews
- Single-gene SCN1A testing
GeneReviews calls single-gene testing rarely useful and typically not recommended. If used, sequencing comes first, followed by deletion/duplication analysis when no variant is found.GeneReviews
Children with an SCN1A pathogenic variant
- Reading a positive result
Among 182 SCN1A carriers, Dravet syndrome followed in 85% with onset by 6 months, 51% at 6 to 12 months and none later.Cetica 2017 SCN1A carrier study
- Parental testing
GeneReviews cites parental testing showing the variant was de novo in 76 of 80 children with Dravet syndrome.GeneReviews
Children with a negative SCN1A result
- When no SCN1A variant is found
ILAE treats a missing SCN1A or other causal variant as an alert, not an exclusion, calling for caution and consideration of other conditions.ILAE diagnostic criteria
- Where genetic testing is unavailable
The ILAE 2022 position statement gives criteria for diagnosing syndromes in resource-limited regions where EEG, MRI or genetic testing may be unavailable.ILAE 2022 position statement
Where testing goes wrong
- SCN1A sequencing alone misses exon and whole-gene deletions, which account for 8% to 27% of detectable variants per GeneReviews.GeneReviews
- GeneReviews cites MLPA finding copy number changes in 12.5% of patients with Dravet syndrome and no sequencing variant.GeneReviews
- A normal brain MRI at diagnosis is expected; the consensus reached full physician agreement that the initial MRI is typically normal.2022 international consensus
- Abnormal MRI was documented in only 11% of a UK cohort, mostly nonspecific atrophy or hippocampal changes.Brunklaus 2012 UK cohort
- A normal EEG in the first year does not argue against the diagnosis, since interictal discharges appear in fewer than half before 12 months.2022 international consensus
- Guerrini and colleagues reported seizure worsening in 17 of 21 patients with severe myoclonic epilepsy treated with lamotrigine.Guerrini 1998 lamotrigine report
- The consensus linked longer early use of contraindicated sodium channel blockers, including lamotrigine, with poorer developmental outcome.2022 international consensus
- ILAE lists efficacy of sodium channel blocking antiseizure medicines as an alert that should prompt caution about the diagnosis.ILAE diagnostic criteria
- An SCN1A variant does not by itself mean Dravet syndrome, since milder phenotypes such as GEFS+ share the gene.GeneReviews
- McIntosh and colleagues found vaccination may bring onset earlier, but saw no effect of vaccination on intellectual outcome or seizure type.McIntosh 2010 vaccination study
- ILAE lists onset at 1 to 2 months or 15 to 20 months, and impairment present at seizure onset, as diagnostic alerts.ILAE diagnostic criteria
Where to test
- NIH Genetic Testing Registry: Dravet syndrome: Lists SCN1A tests and epilepsy multigene panels submitted by laboratories. NIH does not independently verify submissions or endorse any laboratory.NIH GTR
- Labcorp Invitae Unlock Epilepsy Program: Covers US children under 18 who have had an unprovoked seizure, billing insurance first. Patients without coverage may qualify for sponsored no-charge testing, and de-identified data may go to commercial entities. The program page does not name who sponsors the no-charge option, and febrile seizures alone may not meet its unprovoked seizure criterion.Invitae Unlock Epilepsy page
Family screening and referral
Who else in the family
- SCN1A seizure disorders are autosomal dominant, and each child of an affected person has a 50% chance of inheriting the variant.GeneReviews
- GeneReviews notes the risk of seizures in a child who inherits the variant is under 100%, because penetrance is reduced.GeneReviews
- Only approximately 5% of probands with Dravet syndrome have a parent with the same SCN1A variant, according to GeneReviews.GeneReviews
- Parents who carried the variant of a child with Dravet syndrome were either asymptomatic or had mild epilepsy, in studies GeneReviews cites.GeneReviews
- More than 95% of people with GEFS+ have a parent with the same SCN1A variant, so family patterns differ by phenotype.GeneReviews
- Prenatal diagnosis is possible for pregnancies at increased risk once the family SCN1A variant is known, per GeneReviews.GeneReviews
Who to refer to
- GeneReviews says care is best provided by a physician, such as a pediatric epileptologist, familiar with the pharmacotherapy for this disorder.GeneReviews
- In a Biocodex-supported European survey, emergency rooms were the most frequent first contact, yet no patient was referred to an expert center then.DS'coverED European survey
- The same survey linked diagnostic delays mainly to late referral to expert centers and long access or turnaround times for genetic testing.DS'coverED European survey
- The consensus panel identified a competent adult provider who understands Dravet syndrome as key to transition, with 95% physician agreement.2022 international consensus
- GeneReviews notes that its family risk guidance does not substitute for consultation with a genetics professional.GeneReviews
Find a specialist by state
From the CMS NPI Registry, a public directory of US clinicians by registered specialty. A listing is not an endorsement and says nothing about experience with Dravet syndrome; patient organizations and academic centers can often name experienced clinicians.
ICD-10-CM codes for Dravet syndrome
For orders, referrals and prior authorization. Each code is checked daily against NLM's ICD-10-CM service.
Once the diagnosis is confirmed
For the patient: why your doctor ordered this test
Plain language a patient can read or take home.
Your doctor ordered this test because your child's seizures could be a sign of Dravet syndrome, a rare type of epilepsy.
Dravet syndrome usually starts in the first year of life, often with long seizures during a fever or after shots.
Most children with Dravet syndrome have a change in a gene called SCN1A. A blood or saliva sample can be tested for it.
The test often checks many epilepsy genes at once, because other gene changes can cause similar seizures.
A normal brain scan or brain wave test is common in babies with Dravet syndrome, so these tests cannot rule it out.
Some seizure medicines can make Dravet seizures worse, which is a big reason an early answer helps your child's doctors.
The gene change is usually new in the child, but parents may be offered testing too, and a genetic counselor can explain the results.
Questions clinicians ask about Dravet syndrome testing
Which combinations of findings should prompt testing for Dravet syndrome?
In published screening and biopsy studies, the highest yields came from SCN1A pathogenic variant plus first seizure before age 6 months (85% of SCN1A variant carriers with seizures, from an Italian cohort of 182 carriers ascertained after seizure onset), and from encephalopathy with refractory seizures plus first seizure within 72 hours of a vaccination (78.6% of patients, 14 in all, with alleged vaccine encephalopathy whose first seizure came within 72 hours of vaccination). Among patients already diagnosed, the most common combination began with seizures that worsen on lamotrigine, seen in 80% of patients with severe myoclonic epilepsy, the older name for Dravet syndrome, aged 2 to 18 and given lamotrigine. These figures describe study groups, not any one patient's chance of having Dravet syndrome.
When should genetic testing for Dravet syndrome be ordered?
The 2022 international consensus strongly supports testing developmentally normal infants aged 2 to 15 months after a first prolonged hemiclonic seizure or convulsive status epilepticus. That applies with fever or after vaccination, when no other cause is found. Strong consensus also covers recurrent prolonged convulsive seizures in the same age range.
Which genetic test is preferred for suspected Dravet syndrome?
An epilepsy multigene panel is preferred, according to 90% of consensus physicians when its cost is similar to SCN1A testing. GeneReviews recommends a panel that includes deletion/duplication analysis and calls single-gene SCN1A testing rarely useful. SCN1A pathogenic variants are found in more than 85% of people with Dravet syndrome.
Does a normal EEG or MRI rule out Dravet syndrome?
No, the consensus says the initial MRI is typically normal and the EEG background is usually normal before 12 months. Interictal discharges appear in most cases only by age 5 years. ILAE calls MRI highly recommended to exclude other causes, but not required for diagnosis.
Why do sodium channel blockers matter when Dravet syndrome is suspected?
ILAE's diagnostic manual cautions that antiseizure medicines with sodium channel blocking properties may aggravate seizures in Dravet syndrome. GeneReviews lists worsening on carbamazepine, oxcarbazepine, phenytoin or lamotrigine as a suggestive feature. Guerrini and colleagues reported worsening in 17 of 21 patients given lamotrigine.
Do vaccines cause Dravet syndrome?
No, the studies cited here point to an underlying SCN1A variant, with vaccination at most bringing seizure onset earlier. Berkovic and colleagues found de novo SCN1A variants in children labeled with vaccine encephalopathy. McIntosh and colleagues found no effect of vaccination on intellectual outcome or later seizure type.
What is the ICD-10 code for Dravet syndrome?
ICD-10-CM codes Dravet syndrome as G40.833, intractable with status epilepticus, and G40.834, intractable without status epilepticus, per NLM's lookup checked November 10, 2026. Orphanet lists Dravet syndrome under ORPHA:33069 and maps it more broadly to ICD-10 G40.4.
Sources
- International consensus on diagnosis and management of Dravet syndrome. Epilepsia 2022;63(7):1761-1777 (Wirrell EC et al; supported by the Dravet Syndrome Foundation, several authors report industry consulting), via PubMed Central, 2022-07.
- ILAE classification and definition of epilepsy syndromes with onset in neonates and infants: Position statement by the ILAE Task Force on Nosology and Definitions. Epilepsia 2022;63(6):1349-1397 (Zuberi SM et al), via PubMed abstract, 2022-06.
- Dravet syndrome (DS): Clinical overview. International League Against Epilepsy, EpilepsyDiagnosis.org diagnostic manual, CC BY-SA 4.0, 2024-06-30.
- Dravet syndrome (DS): Diagnostic criteria. International League Against Epilepsy, EpilepsyDiagnosis.org diagnostic manual, CC BY-SA 4.0, 2024-06-30.
- Dravet syndrome (DS): Differential diagnoses. International League Against Epilepsy, EpilepsyDiagnosis.org diagnostic manual, CC BY-SA 4.0, 2024-06-30.
- SCN1A Seizure Disorders. GeneReviews, University of Washington, Seattle, via NCBI Bookshelf (NBK1318); Miller IO, Sotero de Menezes MA, 2022-02-17.
- Incidence of Dravet Syndrome in a US Population. Pediatrics 2015;136(5):e1310-e1315 (Wu YW et al), via PubMed Central abstract; funding and disclosures not seen, 2015-11.
- Prognostic, clinical and demographic features in SCN1A mutation-positive Dravet syndrome. Brain 2012;135(Pt 8):2329-2336 (Brunklaus A et al), via PubMed abstract; funding and disclosures not seen, 2012-08.
- Clinical and genetic factors predicting Dravet syndrome in infants with SCN1A mutations. Neurology 2017;88(11):1037-1044 (Cetica V et al), via PubMed Central, 2017-03-14.
- A screening test for the prediction of Dravet syndrome before one year of age. Epilepsia 2008;49(4):626-633 (Hattori J et al), via PubMed abstract; funding and disclosures not seen, 2008-04.
- Effects of vaccination on onset and outcome of Dravet syndrome: a retrospective study. Lancet Neurology 2010;9(6):592-598 (McIntosh AM et al), via PubMed abstract; funding and disclosures not seen, 2010-06.
- De-novo mutations of the sodium channel gene SCN1A in alleged vaccine encephalopathy: a retrospective study. Lancet Neurology 2006;5(6):488-492 (Berkovic SF et al), via PubMed abstract; funding and disclosures not seen, 2006-06.
- Prevalence of SCN1A-related dravet syndrome among children reported with seizures following vaccination: a population-based ten-year cohort study. PLoS One 2013;8(6):e65758 (Verbeek NE et al; no competing interests declared), via PubMed abstract, 2013-06-06.
- Lamotrigine and seizure aggravation in severe myoclonic epilepsy. Epilepsia 1998;39(5):508-512 (Guerrini R, Dravet C et al), via PubMed abstract; funding and disclosures not seen, 1998-05.
- From first seizure to specific antiseizure medication in Dravet syndrome: Quantifying delays in the DS'coverED study. Epilepsia Open 2026;11(5):1729-1741 (Christodoulou L et al; institutional and financial support from Biocodex, 1 author is a Biocodex employee), via PubMed Central, 2026-08-13.
- Invitae Unlock Epilepsy Program. Labcorp (Invitae), program page; sponsored testing program, sponsor not named on the page, 2026-11-10.
- Dravet syndrome (GTR condition record, MedGen C0751122; 95 test records returned by an NCBI E-utilities search on November 10, 2026). National Center for Biotechnology Information, NIH, 2026-11-10.
- ICD-10-CM search results for "dravet" (Clinical Table Search Service). National Library of Medicine, 2026-11-10.
- SCN1A Variants in vaccine-related febrile seizures: A prospective study. Annals of Neurology 2020;87(2):281-288 (Damiano JA et al), via PubMed abstract; funding and disclosures not seen, 2020-02.
A reference for licensed professionals, checked against its sources on November 10, 2026. It summarizes what the cited guidance says and does not tell anyone how to diagnose or treat a specific patient. Guidelines change; the current guideline and the treating clinician's judgment govern. Trial Friend is an independent information service, not a medical provider.