A popular term for a distinct severe headache of sudden onset, which develops days to weeks before an index episode of intracranial bleeding, typically a subarachnoid haemorrhage–which is seen in 20% to 50% of patients.
Clinical findings It appears within seconds, peaks in minutes, and lasts for hours to days; the headache may be accompanied by nuchal rigidity, decreased consciousness, papilloedema, retinal haemorrhage, 3rd and/or 6th nerve palsy, bilateral leg weakness, nystagmus, ataxia, aphasia, abulia, hemiparesis, left-sided visual neglect.
Aetiology Subarachnoid haemorrhage, cerebral venous sinus thrombosis, arterial (carotid, vertebral) dissection.
Differential diagnosis Acute expansion, dissection, or thrombosis of unruptured aneurysm, venous sinus thrombosis, sexual headaches, benign thunderclap headache
Synonyms Sentinel headache, warning headache, worst headache of my life