Thunderclap Headache

In station 5 you may be asked to assess a patient with a severe sudden headache

HISTORY (3 minutes)

    • S: where, one or both sides
    • O: when did the headache start and how quickly did the headache come on- over seconds, minutes, hours. What were you doing at the time? Have you still got the headache now?
    • C: what’s the pain like
    • R: does the pain move/spread anywhere else
    • A: nausea, vomiting, neck stiffness, rash, photophobia, fits, visual disturbance, fever, collapse, weakness, numbness, speech disturbance
    • T: Do you normally get headaches? Was this the same as/different from your normal headaches? How often do you get headaches? How long do they usually last? When do you get them? What do you do when you get a headache?
    • E: exacerbating/relieving factors including triggers/warning symptoms e.g. lack of sleep, stress, menstruation, hunger, diet, exercise. What treatments have been tried?
    • S: severity scale 1-10. Was it severe within 1 minute? How bad is it now compared with before? Is it getting better/worse?
  • Subarachnoid Haemorrhage: nausea and vomiting, neck stiffness, photophobia, fits, blackouts, drowsy, worst headache ever?, Risk Factors: high BP, polycystic kidney disease, Fx brain haemorrhage, hypermobile joints (Ehlers-Danlos syndrome and Marfans), smoking
  • Intracerebral Haemorrhage: weakness face/arm/leg, numbness, speech, vision, anticoagulants
  • Cerebral Venous Thrombosis: contraceptive pill, pregnant, cancer, dehydration, clotting problem, infection, inflamm condition (visual disturbance, collapse, fits, weakness, speech disturbance)
  • Cervical Artery Dissection: trauma, neck pain, droopy eyelid, small pupil, ringing in ears, (weakness, visual disturbance, speech, swallow)
  • Pituitary apoplexy: abdo pain, dizziness (double vision/visual loss, nausea and vomiting)
  • Early meningitis: fever, rash, meningitis contacts, (nausea and vomiting, neck stiffness, photophobia, drowsy, fits)
  • History of head injury
  • Reversible cerebral vasoconstriction syndromes: history of migraine, postpartum, triptans, SSRIs, cocaine, amphetamines, ecstasy
  • Acute angle closure glaucoma: red eye, halos, abdo pain, visual disturbance
  • Giant cell arteritis: pain on chewing, scalp pain, visual disturbance, proximal muscle stiffness
  • PMH, Dx, Fx, Sx

EXAMINE (3 minutes)

  • Observations including GCS
  • Inspect: rash, photophobia
  • Neck stiffness, Kernig’s sign
  • Neurological examination and gait
  • CNs- acuity, VF, eye movements, pupils e.g. for Horners, fundoscopy
  • Feel the temporal arteries
  • Chest, abdomen if time allows

ICE and EXPLANATION (2 minutes)

A suggested explanation is as follows:

“Because of the nature of your headache I need exclude a serious cause for your headache such as bleeding in the brain.  I’m going to send you for a CT scan in the first instance but the cause is not always seen on CT scan.  If the scan does not reveal the cause, you will need to have a lumbar puncture. Once we know what the cause is, I will refer you to the appropriate specialist for further management”



Causes of thunderclap headache:

  1. Subarachnoid Haemorrhage and sentinel headache
  2. Intracerebral Haemorrhage
  3. Cerebral Venous Thrombosis
  4. Cervical artery dissection
  5. Pituitary apoplexy
  6. Sexual headache
  7. Colloid cyst third ventricle
  8. Reversible cerebral vasoconstriction syndromes
  9. Acute hypertensive crisis with reversible posterior leukoencephalopathy syndrome
  10. Meningitis
  11. Spontaneous intracranial hypotension (CSF leakage from spinal meningeal defects or dural tears)

Others causes of headache (can be severe):

Severe migraine: aura, sensitivity to light/noise/smell

Tension type headache: stress/anxiety/depression/neck tightness

Cluster: watering red eye

Sinusitis: coryzal symptoms

Trigeminal Neuralgia

Subdural Haemorrhage

Substance abuse/withdrawal, medication overuse headache

Raised intracranial pressure e.g.secondary to space occupying lesion





  1. Non contrast CT brain
  2. LP if CT head is normal. This should include measurement of opening pressure, routine CSF analyses including cell counts and xanthochromia
  3. If head CT and CSF studies are non-diagnostic, brain MRI and imaging of the cerebral vasculature with MR angiography and MR venography should be performed. If MR imaging is not an option, perform CT angiography and CT venography.




The management depends on the underlying aetiology.


Written by Dr Sarah Kennedy


Resources used include those listed in the references section of this webpage and also: