SNOOP4

Mnemonic for red flags suggesting secondary (dangerous) headache etiology

Indication

id: systemic; label: S — Systemic symptoms (fever, weight loss, cancer history, HIV, pregnancy); type: yesno
id: neuro; label: N — Neurological symptoms or signs (focal deficits, papilledema, altered mental status); type: yesno
id: onset; label: O — Onset sudden ("thunderclap" — maximal intensity within seconds); type: yesno
id: older; label: O — Older age (new headache onset after age 50); type: yesno
id: pattern; label: P — Pattern change (progressive worsening, new daily persistent, postural); type: yesno
id: precipitated; label: P — Precipitated by Valsalva, exertion, or position change; type: yesno
id: papilledema; label: P — Papilledema or visual symptoms; type: yesno
id: positional; label: P — Positional component (worse lying down or standing); type: yesno

function(score) { if (score === 0) return { risk: '0/8 Red Flags', tier: 'No Red Flags', action: 'Low probability of secondary headache. Consider primary headache diagnosis (migraine, tension, cluster). Outpatient management appropriate.', color: 'green' }; if (score <= 2) return { risk: score + '/8 Red Flags', tier: 'Red Flags Present', action: 'Secondary headache possible. Targeted workup based on specific flags: CT/CTA for thunderclap, MRI for focal neuro signs, LP if meningitis/SAH suspected.', color: 'yellow' }; return { risk: score + '/8 Red Flags', tier: 'Multiple Red Flags', action: 'High concern for secondary headache. Urgent imaging (CT \u00B1 CTA/CTV). Consider LP. Broad workup. Neurology consultation.', color: 'red' }; }

Thunderclap headache = SAH until proven otherwise — CT head then LP if CT negative and < 6 hours
New headache in patient > 50: consider giant cell arteritis (check ESR, CRP)
Positional headache worse upright: consider CSF leak; worse supine: consider raised ICP