Reasoning GP · Algorithm · 1-page summary
Facial pain
For: adults with facial or jaw pain in primary care. Not for: facial trauma, or headache without a facial component (headache algorithm). Dental treatment → dentist or NHS 111 dental pathway; GP care does not replace it.
Core rule: in anyone aged 50+ with jaw pain on chewing or temporal tenderness, think GCA and start prednisolone today — a normal ESR or CRP does not exclude it; and never call pain "dental" or "sinus" without testing facial sensation.
0Stop — call 999 now
- Sudden severe one-sided facial pain + ipsilateral Horner syndrome + neck pain (carotid dissection) → 999. No antiplatelet or anticoagulant before imaging.
- Proptosis, ophthalmoplegia/diplopia, ptosis, chemosis or visual loss, especially with fever or sinus/dental infection (cavernous sinus thrombosis, orbital apex) → 999
- Floor-of-mouth swelling, trismus, dysphagia, drooling, voice change or airway concern after toothache (Ludwig's angina) → 999. Do not delay for imaging.
- GCA with visual loss or amaurosis fugax → Same-day emergency ophthalmology or acute assessment + prednisolone now.
1Triage — pain pattern points to the cause
| Pattern | Features → think |
|---|---|
| Seconds | Electric shock, touch-triggered, no deficit → trigeminal neuralgia (TN) |
| On chewing | Settles with rest, age 50+ → GCA until proved otherwise |
| 15–180 min | Orbital, autonomic features, restless → cluster headache |
| Constant / other | With numbness or neuro signs → tumour (block 2); hot/cold or biting → dental; jaw click → TMD; bending forward → sinusitis |
2Screen — one row is enough
- Age 50+, jaw claudication or temporal tenderness → prednisolone 60 mg today + Same-day GCA pathway; do not wait for ultrasound, biopsy or bloods.
- Painful red eye + blurred vision or haloes ± headache, vomiting (acute angle closure) → Same-day eye emergency; no dilating drops.
- Persistent facial numbness or abnormal neurological signs → Urgent neuroimaging via the suspected cancer pathway (NG127).
- Vesicles V1/V2/V3 or ear → aciclovir ≤72 h. Red eye, visual symptoms or Hutchinson sign → Same-day ophthalmology; ear + facial palsy (Ramsay Hunt) → Same-day ENT.
- Rapidly spreading facial swelling or systemic dental infection → Same-day maxillofacial or hospital; not oral antibiotics alone.
- One-sided pain + epistaxis, trismus, neck nodes or loose teeth; parotid mass → Urgent ENT (local head and neck pathway).
- Atypical TN: sensory loss, bilateral, onset <40, MS features, ear symptoms, pain between attacks → Urgent specialist + MRI
3Assess
☐ Facial sensation V1–V3, cranial nerves VI, VII ☐ Temporal arteries ☐ Teeth: percussion, cold test ☐ TMJ, mouth opening ☐ Sinuses, skin vesicles, floor of mouth, neck nodes
Bloods if GCA suspected: FBC, ESR, CRP, U&E, LFTs, glucose — never delay steroids. OPG via dentist; no CT for acute sinusitis.
4Classify — only if the screen is negative
- Dental — localised, hot/cold or biting, percussion-tender tooth → dentist / NHS 111 dental.
- TN — paroxysms in V2/V3, triggered by touch, no deficit between attacks → carbamazepine; MRI via local pathway.
- TMD — pre-auricular pain, click, muscle tenderness, worse chewing → conservative care.
- Sinusitis — cheek/frontal pressure, nasal symptoms after a cold → NG79.
- Post-herpetic neuralgia or persistent idiopathic facial pain — only after red flags excluded.
- Uncertain — say so; re-examine sensation and nerves, then the specialist route by site.
5Treat today — doses: NICE/SPC, BNF, local formulary
- TN: offer carbamazepine 100 mg once or twice daily, titrate slowly. First: FBC, LFTs, U&E, sodium, pregnancy considerations; HLA-B*1502 if Han Chinese or Thai. Rash → stop, specialist advice.
- Dental: paracetamol + ibuprofen (no NSAID in pregnancy, significant CKD, peptic ulcer, anticoagulation). Antibiotics only for spreading infection, systemic illness, trismus, high-risk immunocompromise, or no dental access with risk of progression: amoxicillin (metronidazole if allergic).
- Sinusitis: ≤10 days no antibiotic; ≥10 days → consider high-dose nasal steroid 14 days; no or back-up antibiotic.
- Cluster: offer oxygen 100% ≥12 L/min (non-rebreathing mask) and/or SC or nasal triptan; no oral triptan or opioid. TMD: soft diet, jaw rest, heat, analgesia.
6Refer routinely
- Carbamazepine ineffective, not tolerated or contraindicated → specialist advice; consider early pain/specialist service (CG173).
- First or atypical cluster headache → specialist diagnostic review.
- TMD with locking, severe restriction or failed conservative care → maxillofacial.
- Chronic sinusitis despite 3 months nasal steroid + saline → ENT.
7Never reassure by
- A normal ESR or CRP when GCA is suspected.
- "Dental" or "TMJ" jaw pain in someone 50+ without asking about claudication.
- A good response to carbamazepine — it does not confirm TN.
- Sinus or dental disease before facial sensation is checked.
- Oral antibiotics alone for spreading facial or floor-of-mouth swelling.
8Safety-net — say it, then document it
999 “Call 999 for swelling under the tongue or in the neck, trouble swallowing or breathing, drooling or voice change; a bulging or swollen eye, double vision, loss of sight, or a painful red eye with blurring or haloes; or sudden face and neck pain with a droopy eyelid.” A&E now (aged 50+) “Jaw pain on chewing that stops with rest, new temple headache, scalp tenderness or any sudden change in vision — A&E now, do not wait.” Same day: “On carbamazepine: a rash, fever, sore throat, mouth ulcers or bruising — stop it, call us today. Spreading facial swelling or fever with toothache — today.”
✓Safe to leave primary care only if — all five, documented
No block 0–2 row applies
GCA considered and documented if aged 50+
Facial sensation and cranial nerves recorded
Dentist, MRI or specialist route arranged as needed
Safety-net given; review booked (TN 4–6 weeks)
Summary of the full Reasoning GP facial pain algorithm, which holds the history, examination, investigation and follow-up detail. Sources: NICE NG127; NICE CG173; NICE CG150; NICE NG79; NICE NG12 (updated April 2026); BSR GCA guideline 2020; EAN TN guideline 2019; MHRA (carbamazepine, HLA-B*1502); PCDS herpes zoster. Clinical reference — follow local pathways and check doses: NICE/SPC, BNF.