Kejang Demam
Published on August 7, 2026
Risk Factors
Age 6 months to 5 years, family history of febrile seizures or epilepsy, recent vaccination (DPT, MMR), rapid temperature rise, low-grade fever at seizure onset (<39 C)
Etiology
Seizure provoked by fever (>38 C by any method) from an extracranial source; NOT caused by intracranial infection, electrolyte disturbance, or metabolic derangement
Presentation
A previously healthy child between 6 months and 5 years presents with a generalized tonic-clonic seizure during a febrile illness (commonly upper respiratory infection, otitis media, or roseola)
Classic Exam
Fever, postictal drowsiness that resolves quickly, normal neurological exam after the event; absence of meningeal signs, absence of focal deficits
Diagnostics
Clinical diagnosis. Labs are not routine. Lumbar puncture only if meningeal signs are present. EEG not indicated unless seizure is focal. Neuroimaging not routine for simple febrile seizures.
Management
Acute: diazepam rectal 0.5 mg/kg (or IV 0.2-0.5 mg/kg). Fever control: paracetamol 10-15 mg/kg q4-6h or ibuprofen 5-10 mg/kg 3-4x/day. Intermittent prophylaxis with oral diazepam 0.3 mg/kg TID during fever episodes if indicated. Maintenance therapy (valproic acid or phenobarbital) reserved for select cases only.
Keywords
"Seizure with fever," "generalized tonic-clonic in a toddler," "postictal and back to normal," "self-limited," "no meningeal signs," "normal development"
01Pathophysiology
Febrile seizures arise from an age-dependent vulnerability of the immature brain to the effects of fever. The developing central nervous system in children aged 6 months to 5 years has a lower seizure threshold compared to older children and adults. This is due to a relative excess of excitatory neurotransmission (primarily glutamate) and immature inhibitory pathways (primarily GABA, gamma-aminobutyric acid). When body temperature rises above 38 C, the combination of these developmental factors with fever-induced neuronal hyperexcitability triggers a seizure.
It is critical to understand that the seizure is provoked by the fever itself, not by the underlying infection. The cause of fever is extracranial (viral upper respiratory infection, otitis media, roseola infantum, post-vaccination fever). The IDAI guideline explicitly states that seizures caused by intracranial processes (meningitis, encephalitis) are excluded from this diagnosis. Similarly, if a child has a history of unprovoked seizures (seizures without fever), a seizure during a febrile episode should not be classified as a febrile seizure.
The pathophysiology also explains why the prognosis is excellent. Because the seizure is a functional consequence of the immature brain reacting to fever rather than a structural lesion, neurological development remains normal in children who were previously normal. The IDAI guideline states that disability as a complication of febrile seizures has never been reported. However, prolonged febrile seizures (status epilepticus from febrile seizure) can cause neuronal injury, particularly affecting recognition memory through hippocampal damage, which underscores the importance of promptly terminating any seizure that threatens to become prolonged.
The connection between the status epilepticus guideline and febrile seizures is direct: if a febrile seizure lasts beyond 5 minutes of initial treatment and progresses beyond 30 minutes of continuous or intermittent seizure activity without recovery of consciousness, it meets criteria for status epilepticus (SE). Status epilepticus is driven by a failure of the brain's inhibitory mechanisms (GABA receptor internalization) and an overactivation of excitatory pathways (glutamate, acetylcholine), leading to self-sustaining seizure activity. This is a neurological emergency requiring escalating pharmacotherapy.
02Classification and Clinical Manifestation
The IDAI guideline divides febrile seizures into two categories. This distinction is the single most important clinical classification for exam questions because it determines the workup, treatment, and prognosis.
Duration
Simple Febrile Seizure
< 15 minutes (most < 5 min)
Complex Febrile Seizure
> 15 minutes
Seizure Type
Simple Febrile Seizure
Generalized (tonic, clonic, or tonic-clonic)
Complex Febrile Seizure
Focal/partial, or generalized preceded by focal onset
Recurrence within 24h
Simple Febrile Seizure
Does not recur within 24 hours
Complex Febrile Seizure
Recurs 2 or more times within 24 hours
Proportion
Simple Febrile Seizure
~80% of all febrile seizures
Complex Febrile Seizure
~20%
Post-ictal state
Simple Febrile Seizure
Brief, child returns to baseline quickly
Complex Febrile Seizure
May be prolonged; focal deficits (Todd paralysis) possible
Prognosis
Simple Febrile Seizure
Excellent; no neurological sequelae
Complex Febrile Seizure
Higher risk for recurrence and for later epilepsy
Feature | Simple Febrile Seizure | Complex Febrile Seizure |
|---|---|---|
Duration | < 15 minutes (most < 5 min) | > 15 minutes |
Seizure Type | Generalized (tonic, clonic, or tonic-clonic) | Focal/partial, or generalized preceded by focal onset |
Recurrence within 24h | Does not recur within 24 hours | Recurs 2 or more times within 24 hours |
Proportion | ~80% of all febrile seizures | ~20% |
Post-ictal state | Brief, child returns to baseline quickly | May be prolonged; focal deficits (Todd paralysis) possible |
Prognosis | Excellent; no neurological sequelae | Higher risk for recurrence and for later epilepsy |
Prolonged seizure is a seizure lasting more than 15 minutes, or repeated seizures (more than 2 episodes) with loss of consciousness between events. Prolonged seizures occur in about 8% of febrile seizure cases.
Focal seizure is defined as a seizure involving one side of the body (partial), or a generalized seizure preceded by a partial onset.
Recurrent seizure within 24 hours means two or more seizure episodes in a single day, with the child regaining consciousness between episodes. This occurs in about 16% of febrile seizure cases.
A febrile seizure is classified as complex if any one of these three features is present. A vignette does not need all three.
03Diagnostic Workup
Routine blood work (CBC, electrolytes, glucose)
Indication
Not routine. Perform only to evaluate the source of fever.
Evidence Level
Level 2 / Recommendation B
Lumbar puncture
Indication
Only if meningeal signs present, clinical suspicion of CNS infection, or prior antibiotic use that could mask meningitis signs
Evidence Level
Level 2 / Recommendation B
EEG
Indication
Not indicated, UNLESS the seizure is focal
Evidence Level
Consensus UKK Neurologi IDAI 2016
Neuroimaging (CT or MRI brain)
Indication
Not routine for simple febrile seizures. Only if persistent focal neurological deficit (e.g., hemiparesis, cranial nerve palsy).
Evidence Level
Level 2 / Recommendation B
Test | Indication | Evidence Level |
|---|---|---|
Routine blood work (CBC, electrolytes, glucose) | Not routine. Perform only to evaluate the source of fever. | Level 2 / Recommendation B |
Lumbar puncture | Only if meningeal signs present, clinical suspicion of CNS infection, or prior antibiotic use that could mask meningitis signs | Level 2 / Recommendation B |
EEG | Not indicated, UNLESS the seizure is focal | Consensus UKK Neurologi IDAI 2016 |
Neuroimaging (CT or MRI brain) | Not routine for simple febrile seizures. Only if persistent focal neurological deficit (e.g., hemiparesis, cranial nerve palsy). | Level 2 / Recommendation B |
Laboratory tests are not part of the diagnostic criteria for febrile seizures and should not be ordered reflexively. The IDAI guideline is clear: labs are performed to identify the source of fever, not to diagnose the seizure itself. If a clinician suspects dehydration, electrolyte imbalance, or a bacterial source, targeted labs (peripheral blood count, electrolytes, blood glucose) are appropriate. But a child with an obvious viral URI and a classic simple febrile seizure does not need a blood draw.
Lumbar puncture (LP) is the test that exam questions most frequently focus on. The older teaching was that LP should be performed routinely in all children under 12-18 months. The 2016 IDAI guideline, consistent with the updated AAP 2011 recommendations, no longer recommends routine LP for children under 12 months with a simple febrile seizure and a good general condition. LP is now indicated only when:
There are signs or symptoms of meningeal irritation (neck stiffness, Kernig sign, Brudzinski sign).
There is clinical suspicion of CNS infection based on history and examination.
The child has received prior antibiotics, which may mask the clinical presentation of meningitis.
This is a high-yield testing point. The exam will present a well-appearing 10-month-old with a simple febrile seizure, no meningeal signs, and a clear source of fever. The correct answer is observation and parental reassurance, not LP.
EEG is not indicated for febrile seizures. The only exception is a focal seizure, where EEG is performed to identify a structural epileptic focus in the brain that requires further evaluation. An EEG performed after a simple febrile seizure may show nonspecific abnormalities that do not predict epilepsy and lead to unnecessary anxiety and treatment.
Neuroimaging (CT or MRI of the brain) is not routinely performed for simple febrile seizures. The IDAI guideline reserves imaging for children with persistent focal neurological deficits such as hemiparesis or cranial nerve palsy, which suggest a structural brain lesion rather than a benign febrile seizure.
04Management and Treatment
Prehospital (parents)
Intervention
Diazepam rectal
Dose
0.5-0.75 mg/kg; or 5 mg (BW <12 kg) / 10 mg (BW >=12 kg). May repeat once after 5 min. Max 2 doses at home.
Emergency Department
Intervention
Diazepam IV
Dose
0.2-0.5 mg/kg, rate 2 mg/min, max 10 mg
ED alternative
Intervention
Midazolam IM/buccal
Dose
0.2 mg/kg, max 10 mg. Buccal by age: 2.5 mg (6-12 mo), 5 mg (1-5 yr), 7.5 mg (5-9 yr), 10 mg (>=10 yr)
Seizure continues 5-10 min after benzo
Intervention
Phenytoin IV OR Phenobarbital IV
Dose
Phenytoin 20 mg/kg in 50 ml NaCl 0.9% over 20 min (2 mg/kg/min), max 1000 mg. OR Phenobarbital 20 mg/kg IV at 10-20 mg/min, max 1000 mg
Refractory SE (>=60 min)
Intervention
ICU: Midazolam drip, Propofol, or Pentobarbital
Dose
Midazolam bolus 100-200 mcg/kg IV then 100 mcg/kg/hr. Propofol bolus 1-3 mg/kg then 2-10 mg/kg/hr. Pentobarbital bolus 5-15 mg/kg then 0.5-5 mg/kg/hr.
Phase | Intervention | Dose |
|---|---|---|
Prehospital (parents) | Diazepam rectal | 0.5-0.75 mg/kg; or 5 mg (BW <12 kg) / 10 mg (BW >=12 kg). May repeat once after 5 min. Max 2 doses at home. |
Emergency Department | Diazepam IV | 0.2-0.5 mg/kg, rate 2 mg/min, max 10 mg |
ED alternative | Midazolam IM/buccal | 0.2 mg/kg, max 10 mg. Buccal by age: 2.5 mg (6-12 mo), 5 mg (1-5 yr), 7.5 mg (5-9 yr), 10 mg (>=10 yr) |
Seizure continues 5-10 min after benzo | Phenytoin IV OR Phenobarbital IV | Phenytoin 20 mg/kg in 50 ml NaCl 0.9% over 20 min (2 mg/kg/min), max 1000 mg. OR Phenobarbital 20 mg/kg IV at 10-20 mg/min, max 1000 mg |
Refractory SE (>=60 min) | ICU: Midazolam drip, Propofol, or Pentobarbital | Midazolam bolus 100-200 mcg/kg IV then 100 mcg/kg/hr. Propofol bolus 1-3 mg/kg then 2-10 mg/kg/hr. Pentobarbital bolus 5-15 mg/kg then 0.5-5 mg/kg/hr. |
Fever Management and Prophylaxis
Antipyretic
Medication
Paracetamol
Dose
10-15 mg/kg/dose q4-6h
Duration
During febrile illness
Antipyretic
Medication
Ibuprofen
Dose
5-10 mg/kg/dose 3-4x/day
Duration
During febrile illness
Intermittent prophylaxis
Medication
Diazepam oral
Dose
0.3 mg/kg/dose TID (max 7.5 mg/dose)
Duration
First 48 hours of each febrile episode
Intermittent prophylaxis
Medication
Diazepam rectal
Dose
0.5 mg/kg/dose TID
Duration
First 48 hours of each febrile episode
Maintenance therapy
Medication
Valproic acid (preferred)
Dose
15-40 mg/kg/day divided BID
Duration
1 year, discontinue without taper while afebrile
Maintenance therapy
Medication
Phenobarbital (alternative)
Dose
3-4 mg/kg/day in 1-2 doses
Duration
1 year, discontinue without taper while afebrile
Strategy | Medication | Dose | Duration |
|---|---|---|---|
Antipyretic | Paracetamol | 10-15 mg/kg/dose q4-6h | During febrile illness |
Antipyretic | Ibuprofen | 5-10 mg/kg/dose 3-4x/day | During febrile illness |
Intermittent prophylaxis | Diazepam oral | 0.3 mg/kg/dose TID (max 7.5 mg/dose) | First 48 hours of each febrile episode |
Intermittent prophylaxis | Diazepam rectal | 0.5 mg/kg/dose TID | First 48 hours of each febrile episode |
Maintenance therapy | Valproic acid (preferred) | 15-40 mg/kg/day divided BID | 1 year, discontinue without taper while afebrile |
Maintenance therapy | Phenobarbital (alternative) | 3-4 mg/kg/day in 1-2 doses | 1 year, discontinue without taper while afebrile |
Acute seizure at home (prehospital): Parents should administer diazepam rectally if the seizure lasts more than 5 minutes. The IDAI guideline permits parents to give one dose of rectal diazepam at home. If the seizure does not stop, or if the seizure lasts more than 5 minutes total, the child should be brought to the hospital. Parents should NOT insert anything into the child's mouth, should position the child on their side, loosen tight clothing, observe and time the seizure, and stay with the child.
Acute seizure in the ED: If the child arrives still seizing, diazepam IV at 0.2-0.5 mg/kg (rate 2 mg/min, max 10 mg) is the fastest-acting option. If IV access is not available, midazolam can be given IM or buccal at 0.2 mg/kg. If seizure persists 5-10 minutes after the benzodiazepine, the algorithm branches into two equivalent pathways: phenytoin IV or phenobarbital IV. If one is used first and seizure continues, the other is used second. This two-drug approach is standard before escalating to refractory SE management.
Antipyretics: The IDAI guideline makes an important evidence-based statement: there is no evidence (Level of Evidence 1, Recommendation A) that antipyretics prevent recurrence of febrile seizures. Despite this, Indonesian pediatric neurologists recommend giving antipyretics for comfort. Paracetamol at 10-15 mg/kg every 4-6 hours or ibuprofen at 5-10 mg/kg 3-4 times daily are used. Antipyretics treat the fever but do NOT prevent the seizure.
Intermittent prophylaxis refers to giving diazepam only during febrile episodes, not continuously. Indications include: severe neurological abnormality (e.g., cerebral palsy), four or more recurrences per year, age under 6 months, seizure at temperature below 39 C, or rapid temperature rise in a prior episode. Diazepam is given orally at 0.3 mg/kg TID or rectally at 0.5 mg/kg TID for the first 48 hours of fever. Parents must be counseled that this dose can cause ataxia, irritability, and sedation.
Continuous (maintenance) therapy is reserved for highly selective cases (Level of Evidence 3, Recommendation D). Three indications: focal seizure, prolonged seizure (>15 min), or clear neurological abnormality before or after the seizure (cerebral palsy, hydrocephalus, hemiparesis). Developmental delay alone is NOT an indication. The drug of choice is valproic acid at 15-40 mg/kg/day BID. Phenobarbital is an alternative but causes behavioral disturbance and learning difficulty in 40-50% of cases. Treatment lasts 1 year and is stopped without tapering while the child is afebrile. Maintenance therapy does NOT prevent the later development of epilepsy.
05Differential Diagnosis and Distractors
Meningitis / Encephalitis
Why It Looks Similar
Fever + seizure in a young child
Key Discriminator
Meningeal signs present (neck stiffness, Kernig, Brudzinski); altered consciousness that does NOT resolve postictally; toxic-appearing child; CSF pleocytosis on LP
Epilepsy
Why It Looks Similar
Recurrent seizures in a young child
Key Discriminator
Seizures occur WITHOUT fever; or the child has a history of unprovoked seizures. If a child has known unprovoked seizures and then seizes during fever, it is not classified as febrile seizure.
Febrile status epilepticus
Why It Looks Similar
A febrile seizure that does not stop
Key Discriminator
Duration > 30 min of continuous seizure or repeated seizures without recovery of consciousness. Still within the febrile seizure spectrum but requires SE protocol.
Electrolyte disturbance (hyponatremia, hypoglycemia, hypocalcemia)
Why It Looks Similar
Seizure in a febrile, vomiting/dehydrated child
Key Discriminator
Labs reveal the metabolic cause. Febrile seizure by definition is NOT caused by electrolyte or metabolic derangement.
Shaking rigor
Why It Looks Similar
Whole-body shaking during high fever
Key Discriminator
Child is conscious during the event; no tonic phase, no postictal state; stops when fever is addressed. NOT a seizure.
Structural epilepsy with fever trigger
Why It Looks Similar
Focal seizure during fever
Key Discriminator
Complex febrile seizure is a diagnosis of exclusion; focal features warrant EEG and potentially imaging to rule out a structural lesion.
Post-vaccination reaction
Why It Looks Similar
Seizure within days of DPT or MMR
Key Discriminator
Still classified as a febrile seizure (vaccine-associated febrile seizure). DPT: 6-9 per 100,000; MMR: 25-34 per 100,000. Vaccination is NOT contraindicated.
Differential | Why It Looks Similar | Key Discriminator |
|---|---|---|
Meningitis / Encephalitis | Fever + seizure in a young child | Meningeal signs present (neck stiffness, Kernig, Brudzinski); altered consciousness that does NOT resolve postictally; toxic-appearing child; CSF pleocytosis on LP |
Epilepsy | Recurrent seizures in a young child | Seizures occur WITHOUT fever; or the child has a history of unprovoked seizures. If a child has known unprovoked seizures and then seizes during fever, it is not classified as febrile seizure. |
Febrile status epilepticus | A febrile seizure that does not stop | Duration > 30 min of continuous seizure or repeated seizures without recovery of consciousness. Still within the febrile seizure spectrum but requires SE protocol. |
Electrolyte disturbance (hyponatremia, hypoglycemia, hypocalcemia) | Seizure in a febrile, vomiting/dehydrated child | Labs reveal the metabolic cause. Febrile seizure by definition is NOT caused by electrolyte or metabolic derangement. |
Shaking rigor | Whole-body shaking during high fever | Child is conscious during the event; no tonic phase, no postictal state; stops when fever is addressed. NOT a seizure. |
Structural epilepsy with fever trigger | Focal seizure during fever | Complex febrile seizure is a diagnosis of exclusion; focal features warrant EEG and potentially imaging to rule out a structural lesion. |
Post-vaccination reaction | Seizure within days of DPT or MMR | Still classified as a febrile seizure (vaccine-associated febrile seizure). DPT: 6-9 per 100,000; MMR: 25-34 per 100,000. Vaccination is NOT contraindicated. |
06Recurrence Risk and Prognosis
Risk Factor | Detail |
|---|---|
Family history of febrile seizures or epilepsy | First-degree relative |
Age at first seizure < 12 months | Younger age = higher recurrence |
Temperature < 39 C at seizure onset | Lower threshold = higher vulnerability |
Short interval between fever onset and seizure | Seizure early in the illness |
First episode was a complex febrile seizure | Any complex feature |
All factors present | ~80% recurrence |
No factors present | 10-15% recurrence |
Peak recurrence period | First year after initial seizure |
Epilepsy Risk Factors
Risk Factor | Individual contribution |
|---|---|
Neurological or developmental abnormality before the first febrile seizure | 4-6% |
Complex febrile seizure | 4-6% |
Family history of epilepsy in a parent or sibling | 4-6% |
Simple febrile seizure recurring >= 4 episodes in one year | 4-6% |
Combined risk factors | 10-49% |
Death directly attributable to febrile seizures has never been reported. Mortality in children with simple febrile seizures and normal development is the same as in the general population.
07Traps and High-Yield Pearls
Trap 1: Ordering LP on every febrile seizure in an infant. The older guideline recommended LP for all children under 12-18 months. The current guideline (AAP 2011 / IDAI 2016) does NOT recommend routine LP for well-appearing infants with simple febrile seizures. LP is indicated only when there are meningeal signs, clinical suspicion of CNS infection, or prior antibiotic use that might mask meningitis. When a vignette gives you a well-appearing 9-month-old with an obvious viral illness and a self-limited generalized seizure, the answer is reassurance, not LP.
Trap 2: Believing antipyretics prevent febrile seizures. The evidence (Level 1) clearly shows that antipyretics do NOT reduce the risk of febrile seizure recurrence. Antipyretics are given for comfort. When a question asks about "preventing future febrile seizures," the answer involves intermittent diazepam prophylaxis for selected patients, not aggressive antipyretic use.
Trap 3: Confusing intermittent prophylaxis versus maintenance therapy. Intermittent diazepam (given only during febrile episodes for 48 hours) is for children with recurrent febrile seizures meeting certain risk criteria. Maintenance therapy (daily valproic acid or phenobarbital for 1 year) is reserved for a much narrower group: focal seizures, prolonged seizures (>15 min), or clear structural neurological abnormality. Developmental delay alone does NOT qualify for maintenance therapy.
Trap 4: Assuming febrile seizures cause epilepsy. The core competency being tested is understanding that febrile seizures are benign and self-limited. Even in children who go on to develop epilepsy, seizure medication given during the febrile seizure period does not alter that trajectory. The guideline is explicit: maintenance therapy cannot prevent the development of epilepsy.
Trap 5: Withholding vaccination. There is no contraindication to vaccination in a child with a history of febrile seizures. The risk of vaccine-associated febrile seizure is low (RR 1.6), and the recommendation is to provide intermittent diazepam and prophylactic paracetamol around vaccination, not to skip the vaccine.
The overarching competency being tested is the ability to distinguish a benign, self-limited condition from a dangerous one (meningitis, epilepsy, status epilepticus) using clinical features alone, to avoid unnecessary testing, and to counsel parents accurately about prognosis and recurrence.