Since the initial description in 1978 [
86] and subsequent reports of Dravet, the clinical features of this disorder are represented by severe myoclonic epilepsy with onset in infancy (SMEI), associated with multiple seizure types, last-during epileptic seizures with frequent episodes of status epilepticus, often triggered by fever [
87,
88]. The incidence is reported as about 1 in 40,000 infants [
89,
90]. In its classical clinical feature, patients affected by this disorder initially growth normally, and seizures begin around the age of 6–8 months trigger by fever, and presenting with either low and high temperature. Seizures are last –during and might have generalized or unilateral expression. Less commonly, seizures might also develop without fever. The EEG might be initially normal or present with diffuse or unilateral slowing after the episodes of prolonged course. There are five principal diagnostic criteria for classical DS: normal developmental before seizure onset; two or more febrile seizures complex before the age of 12 months; myoclonic, hemiclonic or generalized tonic-clonic seizures; two last-during seizures; and refractory seizures after the age of 2-years [
88]. However, in patients with SMEI related to SCN1A gene mutations, some of the above-mentioned clinical signs might be absent, including the different age of onset, type of seizures, EEG pattern, and the non-involvement of intellective capacity [
91‐
94]. For DS linked to SCN1A mutation, the term SCN1A-related epilepsy syndrome has been proposed. This syndrome might also show a wide clinical expression involving not only the brain but also cardiac, hearing, vision, movement issues, urinary, bowel, and endocrine functions [
95]. Psychiatric disturbances and autistic behavioral have frequently been reported [
95]. The EEG typically shows focal or multifocal spike-waves, sharp waves, and slow waves and spikes activity [
88]. In approximately 70–80% of cases, DS is related to a genetic disorder, mostly carrying a de novo SCN1A mutation, and including truncating, missense, and splice- site mutations in 40%, 40%, and 20% of cases, respectively [
96]. Other genes have been associated with DS-like phenotypes, including SCN2A, SCN8A, SCN9A, SCN1B, PCDH19, GABRA1, GABRAG2, STXBP1, HCN1, CHD2, and KCNA2 [
95‐
100]. SCN1A mutations cause an inhibition of the GABAergic inhibitory interneurons, leading to excessive neuronal excitation. This model is referred to as the interneuron hypothesis and is the most accepted mechanism for DS [
96‐
98]. The SCN1A genes encode nine mammalian voltage-gated sodium channel alfa subunits, and their mutation is one of the most common causes of epilepsy detected in 70% to 85% of patients with DS and 3% to 6% of patients with generalized epilepsy with febrile seizures plus (GEFS+) [
91,
97‐
100]. SCN1A haploinsufficiency producing Nav1.1 dysfunction mainly affects GABAergic neurons, which according to the affected site, cortex, cerebellum, basal ganglia, or hypothalamus, are the cause of epileptic seizure, ataxia, crouching gait, thermal dysregulation, and sleep disturbances [
96,
98,
101,
102]. The prognosis for DS is severe for both epileptic seizures and cognitive impairment, and the mortality rate is significant and half of the deaths are recorded as Sudden Unexpected Death (SUDEP) [
103]. DS treatment is based on the use of appropriate drugs. Sodium channel blocking drugs are not advised in cases of DS due to the genetic defects affecting the sodium channels. In most cases, the drugs used in the treatment of DS produce little benefit. Pharmacological treatment attempts have been carried out with oxcarbamazepine, phenytoin, bromides, topiramate, levetiracetam, vigabatrin, stiripentol (STP), valproic acid, clobazam. [
73] The effectiveness of STP was tested in 32 patients affected by DS, 15 of which had SCN1A mutations. The authors found that STP treatment was able to reduce the frequency of seizures in 72 ± 23% of the mutation group, compared to 50 ± 40% of the non-mutation group [
104]. Triple treatment with valproate, topiramate, and STP has been effective in DS case report [
105]. In a study of Myers et al. [
106] performed on 41 patients with DS, treatment with STP displayed a long-term reduction of about 50% of cases both in patients with generalized than those with focal epileptic seizures. In general STP treatment in DS is effective and well-tolerated and markedly reduce the frequency of prolonged seizures [
107]. New drugs have been proposed for the treatment of SD [
108].