It consists of pharmacologic treatment of possible prolonged seizures, and in the prevention of possible recurrences. In most cases, SFS spontaneously ceases within 2–3 min, and does not require treatment. Occasionally SFS may last longer than 3 min; in these cases, pharmacologic treatment is recommended.
4.1.2. Treatment of a prolonged seizure in a home setting
See paragraph 5.4 of the section “Essential Issues for Health Education to Families.”
4.1.3. Prevention and recurrence risk
The general risk of febrile seizure recurrence is estimated at around 30–40% (Knudsen, 2000). The risk factors for recurrence, similar for simple and CFS (Offringa et al., 1994), are:
- 1 Early age of onset (<15 months) (Offringa et al., 1994; Berg et al., 1997; Knudsen, 2000)
- 2 Epilepsy in first-degree relatives (Berg et al., 1997; Knudsen, 2000)
- 3 Febrile seizures in first-degree relatives (Offringa et al., 1994; Berg et al., 1997; Knudsen, 2000)
- 4 Frequent febrile illness (Offringa et al., 1994; Knudsen, 2000)
- 5 Low temperature at the onset of the febrile seizure (Offringa et al., 1994; Berg et al., 1997)
Recurrence frequency is 10% in patients with no risk factors; 25–50% in the presence of 1–2 risk factors; 50–100% in the presence of 3 or more risk factors (Knudsen, 2000). The risk of epilepsy is estimated at around 1–1.5% in patients with SFS (Sapir et al., 2000), only slightly higher than incidence in the general population, which is approximately 0.5%. The risk of epilepsy in subjects with CFS is, instead, estimated between 4 and 15% (Berg & Shinnar, 1996; Sapir et al., 2000).
There is no evidence for therapies to prevent subsequent epilepsy (Baumann & Duffner, 2000; Knudsen, 2000). Several studies, including meta-analyses (Rantala et al., 1997; American Academy of Pediatrics, 1999; Baumann & Duffner, 2000), have demonstrated that continuous administration of phenobarbital and valproic acid is efficacious in preventing SFS recurrence. There are, however, contraindications for administration of these drugs, namely potential side effects, which risk overcoming the benefits of treatment (Sulzbacher et al., 1999). Poor compliance has been described in case of continuous treatment with phenobarbital or valproic acid.
Even intermittent rectal or oral diazepam prophylaxis (Rosman et al., 1993; Fukuyama et al., 1996; Verrotti et al., 2004; Pavlidou et al., 2006), administered at the onset of fever, is efficacious in preventing recurrences. However, even in this case, side effects are unavoidable (transient mild ataxia, hyperactive behavior, or lethargy; in rare cases respiratory depression, bradycardia, or hypotension).
Therefore, given the benign prognosis of SFS, which does not cause permanent damage and tends to spontaneously remit with age, and the potential side effects of anticonvulsive therapy, prophylaxis for SFS recurrences are not recommended (Fukuyama et al., 1996; Rantala et al., 1997; American Academy of Pediatrics, 1999; Baumann & Duffner, 2000; Knudsen, 2000) (class of evidence I). In a restricted group of patients with SFS for whom the seizures are considered as “unacceptable” because of their high frequency, prophylaxis may be indicated. Two possible scenarios should, therefore, be considered (Fukuyama et al., 1996; American Academy of Pediatrics, 1999):
A) Patients with one or more SFS episodes and reliable parents: Active surveillance, following the principle of “wait and see” (Fukuyama et al., 1996); in these cases it is recommended that administration of anticonvulsive therapy be avoided; give parents exhaustive information, including instructions on diazepam administration in the event of prolonged seizures (see section 5); and monitor the natural evolution of seizures (class of evidence I).
B) Patients with at least one of the following conditions:
- 1 Frequent seizures in a short period of time (3 or more in 6 months, 4 or more in one year);
- 2 History of seizures longer than 15 min, or requiring pharmacologic therapy to be stopped;
In these cases intermittent therapy (Rosman et al., 1993; Verrotti et al., 2004; Pavlidou et al., 2006), that is, rectal administration (first choice), or oral administration of diazepam, can be considered as an emergency measure and administered, at the onset of fever, at a dose of 0.4–0.5 mg/kg, to be repeated a second time if fever persists after 8 h. Typically diazepam administration should be limited to two doses, although specific clinical conditions may require a third dose after at least 24 h from the first administration (Fukuyama et al., 1996) (class of evidence II). It should be noted that febrile seizures occur, in 98% of cases, within the first 24 h from the onset of fever; it is, therefore, not justified to extend therapy administration after this period. In case of failure, and, in particular, when parents are unable to promptly recognize the onset of fever, continuous anticonvulsive therapy with phenobarbital or valproic acid may be used (Fukuyama et al., 1996). Phenobarbital should be administered at a dose of 3–5 mg/kg/day in 1–2 intakes. Valproic acid should be administered at a dose of 20–30 mg/kg/day, in 2–3 intakes. Valproic acid is to be preferred, as phenobarbital may provoke, among its various side effects, attention deficit, hyperactivity, and cognitive impairment (Sulzbacher et al., 1999). Carbamazepine and phenytoin have proved to be inefficacious (American Academy of Pediatrics, 1999; Baumann & Duffner, 2000).