SNOOP
Headache Red Flags (Secondary Headache Screen)
Any red flag → imaging or workup before calling it primary.
The board-friendly take on headache is that primary headaches (migraine, tension, cluster) are diagnosed by history once you have screened SNOOP and found nothing. Systemic symptoms (fever, weight loss) or Secondary risk factors (HIV, cancer), Neurologic deficit or seizure, Onset sudden (thunderclap), Older age (new headache after 50), Pattern change or Progressive course — any positive should trigger imaging or further workup before calling it primary. AANP exam vignettes hide one SNOOP feature in an otherwise typical migraine presentation to test whether you order the CT or MRI. Worst headache of life and new headache over 50 are recurring right-answer triggers.
- SSystemic symptoms / Secondary risk factorsFever, weight loss, night sweats, HIV, cancer history, immunocompromise, anticoagulation.
- NNeurologic signs or symptomsFocal deficits, confusion, papilledema, seizure, altered mental status.
- OOnset sudden (thunderclap)Peak intensity within seconds to a minute — think SAH until proven otherwise.
- OOlder age at onset (>50)New or progressive headache after 50 — rule out temporal arteritis (check ESR/CRP), malignancy, and vascular causes.
- PPattern change or Positional / PrecipitatedProgressive crescendo, worse with Valsalva or positional, or triggered by exertion, cough, or sex.
Clinical Context
A negative SNOOP in a typical migraine or tension pattern supports primary headache and skips neuroimaging. A positive SNOOP warrants workup — non-contrast CT for thunderclap (then LP if CT negative and SAH still suspected), MRI for progressive or focal findings, ESR/CRP + temporal artery biopsy for older adults with new headache and jaw claudication or visual changes.
The "thunderclap" and "worst headache of my life" stems are the highest-stakes traps — never empirically treat these as migraine. AANP loves pairing one SNOOP feature with an otherwise migraine-sounding history and asking what to do next: imaging, not triptans.
Related Mnemonics
- ABCD² — TIA Stroke Risk (ABCD² Score)
- AEIOU-TIPS — Causes of Altered Mental Status
- BE FAST — Stroke Recognition (Extended)
- CAM — Delirium Diagnosis (Confusion Assessment Method)
- FAST — Stroke Recognition
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