See also

Seizures: acute management
Sepsis
Adrenal crisis/insufficiency

Key points

1. Infantile Spasms (IS), also known as epileptic spasms, is a type of seizure and often relates to one of the most common severe epilepsy syndromes in infants
2. IS are typically sudden, brief, bilateral and symmetric contraction of the muscles of the neck, trunk and extremities, occurring in clusters
3. Prompt diagnosis and treatment are critical to minimise the developmental impacts
4. First-line treatment is usually high dose prednisolone
5. High dose prednisolone may mask signs of sepsis and increase the risk of adrenal crisis

Background

• Peak age of IS onset is 3 to 7 months but can occur at any age in childhood
• Most children with IS have Infantile Epileptic Spasms Syndrome. Frequently, this is IS accompanied by hypsarrhythmia on EEG and developmental arrest/regression (triad formally known as West syndrome)
• Common causes of IS include tuberous sclerosis complex (TSC), trisomy 21, focal structural abnormalities, and perinatal hypoxic ischaemic encephalopathy (HIE)
• IS are associated with developmental delay in over 80% of infants, and high rates of ongoing epilepsy

Assessment

1. Are the infant's episodes IS?

Encourage parents to record episodes

Features suggestive of IS

• Occur in clusters, usually shortly after waking from sleep
• Typically comprise of sudden flexor or extensor spasms of the whole body
• May be more subtle eg head nodding or facial/ocular movements, especially in early episodes
• Usually symmetric, but may be asymmetric

Differential diagnosis

• Non-epileptic episodes eg shuddering, Sandifer syndrome, sleep myoclonus
• Benign myoclonic epilepsy of infancy
• Other infantile epilepsies

2. What is the underlying cause for IS?

Features that provide potential clues to the underlying cause

• Pre-existing condition known to be associated with IS eg TSC, trisomy 21, HIE
• Family history of seizure disorder or developmental delay (genetic basis)
• Early handedness (focal structural abnormality)
• Dysmorphic features or congenital anomalies (chromosomal abnormality)
• Skin lesions eg hypopigmented macules of TSC
• Pre-existing developmental delay
• Neonatal or early infantile seizures
• Rapid increase in head circumference

Management

Early neurological consultation for all children with suspected IS

Hospital admission should be strongly considered in the instances where it will expedite investigations and commencement of treatment

Investigations

• Urgent awake and sleep EEG
• Prompt MRI brain
• Other investigations for underlying aetiology (if unknown) including genetic testing and urine metabolic screen

Treatment

Treatment will always be led by the treating neurologist

• High dose prednisolone is first-line treatment (except for TSC and treatable metabolic conditions)
  • Dosage and weaning regime should be guided by the treating neurologist
  • High dose prednisolone treatment is associated with increased risk of serious infections and adrenal crises. They should have a steroid alert card as well as a sick day management plan
    • Children with IS who presents febrile or unwell should be managed as per sepsis guidelines as high risk due to immunocompromise
    • If there is vomiting or significant diarrhoea, administer IV/IM hydrocortisone, as these children are at risk of adrenal insufficiency
  • Precautions and monitoring whilst taking prednisolone
    • Monitor blood pressure, glucose and weight twice weekly
    • Consideration of proton pump inhibitor
    • Consideration of prophylactic trimethoprim-sulfamethoxazole for infection prevention
    • Vaccines should be delayed until one month after ceasing prednisolone. See Australian Immunisation Handbook. Consider nirsevimab as per local guidelines due to significant immunosuppression
• Vigabatrin is recommended as first line treatment in TSC
• Combination prednisolone/vigabatrin has a higher rate of spasm cessation, but showed no improvement in developmental outcome at age 18 months over prednisolone alone

Consider consultation with local general paediatric or paediatric neurology team

For all children with suspected IS

Consider transfer when

• Urgent EEG, prompt MRI and neurology consultation are unavailable locally
• The child is requiring care beyond the comfort level of the hospital

For emergency advice and paediatric or neonatal ICU transfers, see Retrieval Services

Consider discharge when

• An admission for IS diagnosis and initial management is usually brief, and discharge is not dependent on spasm cessation
• Child has follow-up arranged with a paediatric neurologist and a follow-up EEG arranged ideally two weeks after treatment initiation.
• A steroid alert card and individualised sick day management plan should be given to parents prior to hospital discharge regarding treatment in the event of becoming unwell

Parent information

Infantile Spasms – For Parents (Paediatric Epilepsy Network NSW)
Kids Health Info - Epilepsy
Hormones and Me – Management of stress steroids

Last updated October 2025