Headache 🧠
Guide to assessing headache in adults: interactive safety screen (high-risk features and Ottawa SAH rule), primary vs secondary causes, and when to escalate.
Headache Safety Screen
Tick any present features — prioritises secondary causes before primary headache treatment
Step 1 — High risk (history)
Any one feature warrants urgent secondary-cause workup.
Step 2 — Ottawa SAH rule
History and examination criteria — complete your exam before excluding SAH. Any criterion present → CT ± LP per pathway.
Step 3 — Consider referral
Lower threshold for imaging and senior review.
Checklists improve safety but are not exhaustive — use clinical judgement, examination (including fundoscopy and neck flexion), and local ED pathways. When in doubt, discuss with a senior.
Safety screen
No screened red flags — primary headache possibleNo high-risk, Ottawa SAH, or referral criteria selected.
May be compatible with primary headache (tension, migraine, cluster) after appropriate history and exam — but screening checklists are not exhaustive. Document review of systems, fundoscopy if indicated, and safety-netting.
Consider
- • Tension-type headache
- • Migraine ± aura
- • Cluster headache
- • Medication-overuse headache
Investigations
- • Investigations guided by exam — not routinely required if low suspicion
- • Reassess if pattern changes or red flags develop
🧭 Clinical workflow
- 1. Safety screen — tick features in the interactive tool above; the outcome sets urgency and suggested next steps.
- 2. History & examination — gather details below and document negative findings. Revisit the screen after exam — Ottawa includes an examination criterion (neck flexion).
- 3. Investigate & escalate — CT head, LP, bloods, and referrals per the outcome branch (see Investigations section).
- 4. Pattern recognition — only if secondary causes are reasonably excluded, compare against primary headache patterns.
- 5. Treat & safety-net — address the cause first; symptomatic treatment for primary headache only when safe.
📞 When called
- Onset and speed — sudden thunderclap vs gradual? Current severity and any change in neurology.
- Vitals and GCS — fever, BP; ask nursing to repeat obs if not recent.
- Trauma, anticoagulation, immunosuppression, or cancer history.
- Has fundoscopy been done? Can neck flexion be assessed on your review?
- Current analgesia, antiemetics, and when last given.
🚨 After the safety screen — how to act
- Any high-risk feature → urgent secondary-cause workup; do not attribute to primary headache without excluding these.
- Ottawa SAH rule: 100% sensitive (low specificity). If any criterion is present → non-contrast CT per local SAH pathway; consider LP if CT is negative and suspicion remains. Absence of all criteria does not exclude SAH if clinical suspicion is high — use judgement.
- Referral flags (immunocompromise, malignancy, unexplained vomiting) → lower threshold for imaging and senior review.
- No flags ticked → primary headache possible after appropriate history and exam, but checklists are not exhaustive.
🧾 History & examination
- History: onset speed, character, location, duration, triggers, aura, sleep, medications (including analgesic overuse), PMH, FHx.
- Vitals and full neurological exam — GCS, cranial nerves, limbs, gait, speech.
- Neck flexion — required for Ottawa SAH rule; document if limited.
- Fundoscopy — papilloedema, disc haemorrhages, or glaucoma signs.
- Temporal arteries if age >50; eye exam if acute glaucoma suspected.
- Document negative red-flag review and examination findings — use Copy on the safety screen for your note.
🔬 Investigations & escalation
- High-risk or Ottawa positive → urgent non-contrast CT head per local SAH pathway; discuss with senior early.
- CT negative but ongoing SAH or meningitis suspicion → discuss LP with senior before discharge.
- Papilloedema or CVST concern → consider CT venography.
- GCA suspected → ESR/CRP; urgent ophthalmology/senior input if visual symptoms — do not delay steroids if vision at risk (per local protocol).
- Acute glaucoma → same-day ophthalmology.
- Referral flags without high-risk features → senior review and lower threshold for CT and neurology input.
- Lower-risk primary headache → investigations usually not required if exam is reassuring; reassess if the pattern changes.
🔍 Don’t forget (differentials)
- Subarachnoid haemorrhage — thunderclap, neck stiffness, LOC.
- Meningitis — fever, photophobia, neck stiffness, rash.
- Raised ICP / SOL — papilloedema, morning headache, vomiting.
- Cerebral venous sinus thrombosis — headache + papilloedema, risk factors.
- Giant cell arteritis — jaw claudication, temporal tenderness, ↑ESR, age >50.
- Cluster headache — severe unilateral periorbital pain with autonomic features.
- Acute glaucoma — painful red eye, blurred vision, halos.
- Optic neuritis — pain with eye movement.
- Medication-overuse headache — daily analgesic use, often morning headache.
📊 Primary headache patterns
- Use only after red flags are excluded and the safety screen outcome allows primary headache workup.
Tension
- Location
- Bilateral
- Quality
- Pressing/tightening
- Intensity
- Mild–moderate
- Duration
- 30 min – continuous
- Associated features
- None typical
- Activity
- Not worsened by routine activity
Migraine
- Location
- Unilateral or bilateral
- Quality
- Pulsating/throbbing
- Intensity
- Moderate–severe
- Duration
- 4–72 h (adults)
- Associated features
- Photophobia, phonophobia, nausea, aura
- Activity
- Aggravated by activity
Cluster
- Location
- Unilateral (periorbital/temporal)
- Quality
- Severe — sharp/boring/burning
- Intensity
- Severe–very severe
- Duration
- 15–180 min
- Associated features
- Ipsilateral lacrimation, nasal congestion, ptosis
- Activity
- Restlessness/agitation
| Feature | Tension | Migraine | Cluster |
|---|---|---|---|
| Location | Bilateral | Unilateral or bilateral | Unilateral (periorbital/temporal) |
| Quality | Pressing/tightening | Pulsating/throbbing | Severe — sharp/boring/burning |
| Intensity | Mild–moderate | Moderate–severe | Severe–very severe |
| Duration | 30 min – continuous | 4–72 h (adults) | 15–180 min |
| Associated features | None typical | Photophobia, phonophobia, nausea, aura | Ipsilateral lacrimation, nasal congestion, ptosis |
| Activity | Not worsened by routine activity | Aggravated by activity | Restlessness/agitation |
💊 Initial management (after excluding red flags)
- Treat cause if secondary headache identified — do not delay imaging/referral for analgesia alone.
- Primary migraine: paracetamol ± NSAID early; consider triptan if typical migraine and no contraindications — check local formulary.
- Antiemetic if vomiting (e.g. metoclopramide/prochlorperazine per local policy).
- Avoid opioid-heavy regimens; warn about medication-overuse headache.
- Cluster: high-flow oxygen and subcutaneous sumatriptan per specialist pathway if diagnosed.
- Safety-net: return if thunderclap, fever, neuro deficit, worst-ever headache, or visual symptoms.
🔗 Related topics
Based on
Note Template
Ready-to-use clinical note structure
🕒 10 / 07 / 2026 — 00:43 ATRP re: headache Patient: [age] [sex] Admission Dx: [reason for admission] PMHx: [migraine, hypertension, malignancy, immunosuppression] 🧾 Hx: • Onset: [sudden / gradual] — character [thunderclap / pulsatile / pressing] • Location, duration, severity, triggers (cough, exertion, posture) • Aura, photophobia, phonophobia, nausea/vomiting • Fever, neck stiffness, visual symptoms, jaw claudication • Medication use / analgesic overuse • Red flags on safety screen: [none / list] 🩺 Exam: • Vitals: HR __ BP __ Temp __ GCS __ • Neuro exam: [normal / deficit] • Neck flexion: [normal / limited] • Fundoscopy: [normal / papilloedema / other] • Temporal arteries / eye exam if indicated 🔬 Investigations: • CT head: [done / planned / not indicated] • Bloods: [FBC, CRP/ESR, glucose — as indicated] • LP: [if SAH/meningitis pathway] 📋 Impression: Headache — [primary migraine/tension/cluster / secondary — specify if known] 📌 Plan: • [Treat cause / analgesia / antiemetic / triptan per protocol] • Safety-net: thunderclap, fever, neuro deficit, visual loss • Referrals: [neurology / ophthalmology / ED — or none] 👤 [Your Name], [Role] IMC: _______