Emergency medicine · 4-minute playbook

Acute headache red flags

Screen for secondary causes before labeling an acute headache as primary.

Red-flag screen

  • Thunderclap onset or maximal intensity within minutes
  • New focal neurologic deficit, altered mental status, seizure, or syncope
  • Fever, meningismus, systemic infection, or immunocompromise
  • Pregnancy or postpartum state
  • Cancer, hypercoagulability, or anticoagulant use
  • New headache after age 50 or a major change in pattern
  • Papilledema or features of raised or low intracranial pressure
  • Recent head trauma, exertional onset, or concern for toxic exposure

A red flag changes the pathway

Select urgent testing and imaging according to the suspected secondary cause, time course, examination, pregnancy status, and local resources. Response to analgesia does not establish a benign diagnosis.