Clinical Commander

Back to dossier
neuro.trigeminal-neuralgia.v1PRODUCTION
neuro.trigeminal-neuralgia.v1

Trigeminal Neuralgia (classic / secondary / idiopathic)

neurologychronicadult
Hard-required inputs
0 / 17
Care setting:

Encounter flow

12/12 authored

Canonical 12-phase frame with authored status for this dossier.

Current phase

Frame

Detailed

Paroxysmal unilateral electric-shock facial pain in a trigeminal distribution, seconds to <2 min, trigger-evoked, with refractory periods — TN until proven otherwise; classify classical / secondary / idiopathic (ICHD-3 PMID 29368949; EAN 2019 PMID 30860637)

Inputs
1
Actions
0
Advance rule
Set
Advance when

Paroxysmal trigeminal-distribution pain pattern confirmed

Patient inputs (25)

Mean onset ~53 y; onset <40 y raises secondary-TN (esp. MS) probability — drives mandatory MRI scrutiny (Maarbjerg PMID 25231219; EAN 2019 PMID 30860637)

AVOID sodium valproate (teratogenic) + carbamazepine teratogenicity considerations; minimise drugs, specialist co-management (EAN 2019 PMID 30860637)

V2/V3 commonest (~69%); isolated/included V1 (ophthalmic) involvement raises secondary-cause probability + corneal-anaesthesia concern (Maarbjerg PMID 25231219; AAN/EFNS PMID 18716236)

Known/suspected MS → secondary TN (younger, often bilateral, refractory); treat the MS — route neuro.ms-flare.core.v1 (EAN 2019 PMID 30860637)

Response to a Na-channel blocker supports TN (89% respond — Maarbjerg PMID 25231219); failure of adequate trial re-opens differential + drives add-on/alternative or surgery

Innocuous-stimulus-evoked paroxysms with refractory periods is a binding diagnostic feature distinguishing TN from odontogenic / TMJ / GCA pain (ICHD-3 PMID 29368949)

Prominent ipsilateral lacrimation/conjunctival injection/rhinorrhoea/ptosis → TAC / SUNCT-SUNA route, not the TN ladder (ICHD-3 PMID 29368949)

Inadequate pain control on optimised medical therapy OR intolerance = surgical-referral trigger — do NOT delay (EAN 2019 PMID 30860637; Barker NEJM 1996 PMID 8598865)

TN paroxysms last a fraction of a second to <2 min; longer continuous pain points to painful trigeminal neuropathy / PIFP / secondary cause (ICHD-3 PMID 29368949)

MRI brain (± MRA, FIESTA/CISS trigeminal protocol) MANDATORY in all TN — exclude secondary cause (MS/tumour/skull-base) + classify classical (NVC + morphological change) vs idiopathic (AAN/EFNS PMID 18716236; EAN 2019 PMID 30860637)

Carbamazepine + oxcarbazepine cause hyponatraemia (SIADH-like) — baseline + monitoring; severe hyponatraemia is an ADR severity trigger (EAN 2019 PMID 30860637)

Carbamazepine/oxcarbazepine/eslicarbazepine/valproate hepatotoxicity — baseline LFT before initiation + periodic monitoring (EAN 2019 PMID 30860637)

Carbamazepine aplastic anaemia / agranulocytosis / leukopenia — baseline CBC + monitoring (AAN/EFNS PMID 18716236)

Bilateral involvement is a secondary-cause red flag (MS, skull-base) — escalates MRI urgency (EAN 2019 PMID 30860637)

Objective trigeminal sensory loss raises secondary-TN probability and suggests painful trigeminal neuropathy — pivot + MRI (AAN/EFNS PMID 18716236; EAN 2019 PMID 30860637)

Inability to eat/drink/take oral medication = acute TN crisis → admission + IV therapy + hydration (EAN 2019 PMID 30860637)

TN ("suicide disease") carries high depression/anxiety/suicidality — screen PHQ-9/GAD-7 + suicide risk; positive screen escalates (NRDP 2024 PMID 38816415)

Where MRI unavailable/equivocal — trigeminal reflex testing is the recommended electrophysiologic surrogate for secondary TN (AAN/EFNS PMID 18716236)

Concomitant continuous pain = TN type 2 (49% — Maarbjerg PMID 25231219); affects therapy expectations + surgical counselling

Han Chinese / SE-Asian / Thai ancestry → HLA-B*15:02 testing before carbamazepine (SJS/TEN risk) (EAN 2019 PMID 30860637)

Carbamazepine serum level for non-response or toxicity assessment (autoinduction lowers levels) (EAN 2019 PMID 30860637)

Carbamazepine/oxcarbazepine/lamotrigine SJS/TEN/DRESS — any evolving rash → STOP drug + urgent evaluation; lamotrigine requires slow titration (EAN 2019 PMID 30860637)

Age >50 + jaw claudication / scalp tenderness / visual symptoms → giant cell arteritis — STAT ESR/CRP + steroids, never delay (route ocular/vision pathway)

Trigger avoidance → reduced oral intake → weight loss / dehydration is a severity marker driving admission (EAN 2019 PMID 30860637)

Renal function for gabapentin/pregabalin dose adjustment (CKD-EPI 2021) + AED clearance in elderly/renal impairment

* = hard-required. Engine cannot meaningfully run until these are filled.

Severity triggers (6)

6 need judgement
  • informationalsevereacute_crisis_unable_to_eat_drink
    Acute TN crisis — pain so severe the patient cannot eat / drink / take oral medication; dehydration / weight loss (EAN 2019 PMID 30860637)
    Trigger could not be auto-evaluated — needs clinician judgement.
  • informationalseveremedically_refractory_or_intolerant
    Inadequate pain control on optimised medical therapy OR intolerance of first-line agents — surgical-referral trigger (EAN 2019 PMID 30860637)
    Trigger could not be auto-evaluated — needs clinician judgement.
  • informationalseveresuicidality_or_severe_depression
    TN ("suicide disease") — positive suicidality screen (PHQ-9 Q9) or severe depression/anxiety (NRDP 2024 PMID 38816415)
    Trigger could not be auto-evaluated — needs clinician judgement.
  • informationalseverecarbamazepine_severe_adr
    Severe carbamazepine/oxcarbazepine hyponatraemia, blood dyscrasia, OR evolving SJS/TEN/DRESS rash (incl. lamotrigine rapid-titration rash) (EAN 2019 PMID 30860637)
    Trigger could not be auto-evaluated — needs clinician judgement.
  • informationalmoderatesecondary_cause_red_flags
    Secondary-TN red flags — bilateral involvement, V1 (ophthalmic) involvement, age <40 at onset, objective trigeminal sensory deficit, abnormal trigeminal reflexes (AAN/EFNS PMID 18716236; EAN 2019 PMID 30860637)
    Trigger could not be auto-evaluated — needs clinician judgement.
  • informationalmoderatems_associated_secondary_tn
    Secondary TN in multiple sclerosis — younger, more often bilateral, frequently refractory to monotherapy (EAN 2019 PMID 30860637; NRDP 2024 PMID 38816415)
    Trigger could not be auto-evaluated — needs clinician judgement.

Workflow calculators

Run this disease's risk and dosing calculators inline.

RISK_STRATIFICATIONoptionalDrives screening
Loading…

Recommended regimen

Trigeminal neuralgia pharmacotherapy — first-line carbamazepine/oxcarbazepine → add-on/alternative → acute-crisis IV (EAN 2019 PMID 30860637; AAN-EFNS 2008 PMID 18721143)
axis: tn_pharmacotherapystep 1 - Step 1 — First-line: carbamazepine or oxcarbazepine (EAN 2019 PMID 30860637; AAN-EFNS 2008 Level A/B PMID 18721143)
Selected step "Step 1 — First-line: carbamazepine or oxcarbazepine (EAN 2019 PMID 30860637; AAN-EFNS 2008 Level A/B PMID 18721143)" — New or under-treated classical / idiopathic TN; no absolute contraindication
  • carbamazepine
    first line
    sodium_channel_blocker_AED
    100–200 mg PO; titrate by 100–200 mg every few days to effect • PO • BID (immediate-release) or per formulation (max: up to 1200 mg/day (typical effective 200–800 mg/day))
    triggers: new_or_undertreated_TN
    First-line, strongest evidence — NNT ~1.7–2.6 for pain relief; ~70% initial response (AAN-EFNS 2008 Level A PMID 18721143; EAN 2019 PMID 30860637). Caveats: HLA-B*15:02 SJS/TEN (test at-risk ancestry), hyponatraemia, aplastic anaemia/agranulocytosis, CYP3A4 autoinduction + many DDIs
    rxcui 2002
  • oxcarbazepine
    first line
    sodium_channel_blocker_AED
    300 mg PO; titrate to 600–1800 mg/day • PO • BID (max: up to 1800 mg/day)
    triggers: first_line_alternative, carbamazepine_intolerant_or_DDI_concern
    Equally effective as carbamazepine for pain, better tolerated, fewer drug interactions, less enzyme induction (EAN 2019 PMID 30860637; AAN-EFNS 2008 Level B PMID 18721143). Hyponatraemia still occurs (often more than CBZ) — monitor Na
    rxcui 32624

outpatient playbook — drug actions (6)

  1. 1. carbamazepine
    rxcui 2002
    100–200 mg PO; titrate to 200–800 mg/day (up to 1200 mg/day) • PO • BID
    trigger: New / under-treated classical or idiopathic TN
    First-line, NNT ~1.7–2.6 (AAN-EFNS 2008 Level A PMID 18721143; EAN 2019 PMID 30860637)
  2. 2. oxcarbazepine
    rxcui 32624
    300 mg PO → 600–1800 mg/day • PO • BID
    trigger: First-line alternative — carbamazepine intolerance / DDI concern / better tolerability desired
    Equally effective, better tolerated, fewer DDIs; monitor Na (EAN 2019 PMID 30860637)
  3. 3. lamotrigine
    rxcui 28439
    25 mg PO with SLOW titration → 200–400 mg/day • PO • BID
    trigger: Refractory / add-on to first-line
    RCT-proven add-on (Zakrzewska Pain 1997 PMID 9415510); slow titration mandatory (SJS/TEN)
  4. 4. baclofen
    rxcui 1292
    5–10 mg PO TID → 50–80 mg/day • PO • TID
    trigger: Refractory / add-on; MS-associated TN
    AAN/EFNS Level C (PMID 18716236); useful in MS-TN
  5. 5. gabapentin or pregabalin
    rxcui 25480
    gabapentin 900–3600 mg/day OR pregabalin 300–600 mg/day (renally adjusted) • PO • TID / BID
    trigger: Na-channel blockers not tolerated; renal-hepatic limits
    Add-on / alternative; renal dose adjustment (calc.ckd_epi_2021)
  6. 6. onabotulinumtoxinA
    rxcui 860189
    intradermal/submucosal injection (~75 U) into pain territory • injection • every ~12 weeks
    trigger: Refractory on medical therapy; surgery declined / awaited
    RCT-proven adjunct (Wu PMID 22492424; Zhang PMID 25263254)

Auto-drafted A&P note

outpatient

Subjective

- Possible entry pathways: Paroxysmal unilateral electric-shock / stabbing facial pain in a trigeminal distribution, fraction-of-second to <2 min (ICHD-3 PMID 29368949; ICOP PMID 32103673); Pain evoked by innocuous stimuli — light touch, chewing, talking, cold air, tooth-brushing, shaving (EAN 2019 PMID 30860637); Concomitant continuous background pain (TN type 2 — 49% of TN; Maarbjerg PMID 25231219).

Objective

- No vitals, labs, or imaging entered for this encounter.

Assessment

**Trigeminal Neuralgia (classic / secondary / idiopathic)** (neuro.trigeminal-neuralgia.v1).
Phenotype framing: Classical (NVC + morphological change) vs secondary (MS/tumour/structural) vs idiopathic; pivot vs odontogenic/TMJ, glossopharyngeal neuralgia, cluster/SUNCT-SUNA, painful trigeminal neuropathy, GCA, PIFP (ICHD-3 PMID 29368949; ICOP PMID 32103673)
Scope: Paroxysmal unilateral electric-shock facial pain in a trigeminal distribution, seconds to <2 min, trigger-evoked, with refractory periods — TN until proven otherwise; classify classical / secondary / idiopathic (ICHD-3 PMID 29368949; EAN 2019 PMID 30860637)

No severity triggers fired against current inputs.

Plan

Regimen axis: **Trigeminal neuralgia pharmacotherapy — first-line carbamazepine/oxcarbazepine → add-on/alternative → acute-crisis IV (EAN 2019 PMID 30860637; AAN-EFNS 2008 PMID 18721143)** — step "Step 1 — First-line: carbamazepine or oxcarbazepine (EAN 2019 PMID 30860637; AAN-EFNS 2008 Level A/B PMID 18721143)".
1. carbamazepine 100–200 mg PO; titrate by 100–200 mg every few days to effect PO BID (immediate-release) or per formulation (sodium_channel_blocker_AED, first line) — First-line, strongest evidence — NNT ~1.7–2.6 for pain relief; ~70% initial response (AAN-EFNS 2008 Level A PMID 18721143; EAN 2019 PMID 30860637). Caveats: HLA-B*15:02 SJS/TEN (test at-risk ancestry), hyponatraemia, aplastic anaemia/agranulocytosis, CYP3A4 autoinduction + many DDIs
2. oxcarbazepine 300 mg PO; titrate to 600–1800 mg/day PO BID (sodium_channel_blocker_AED, first line) — Equally effective as carbamazepine for pain, better tolerated, fewer drug interactions, less enzyme induction (EAN 2019 PMID 30860637; AAN-EFNS 2008 Level B PMID 18721143). Hyponatraemia still occurs (often more than CBZ) — monitor Na

Setting playbook (outpatient) — Primary site — ICHD-3/ICOP diagnosis + MANDATORY MRI (exclude secondary, assess NVC); carbamazepine or oxcarbazepine first-line titration with Na/LFT/CBC monitoring; add-on/alternative for partial response; EARLY neurosurgical referral when refractory/intolerant; screen + manage depression/suicidality (EAN 2019 PMID 30860637)
3. carbamazepine 100–200 mg PO; titrate to 200–800 mg/day (up to 1200 mg/day) PO BID — New / under-treated classical or idiopathic TN (First-line, NNT ~1.7–2.6 (AAN-EFNS 2008 Level A PMID 18721143; EAN 2019 PMID 30860637))
4. oxcarbazepine 300 mg PO → 600–1800 mg/day PO BID — First-line alternative — carbamazepine intolerance / DDI concern / better tolerability desired (Equally effective, better tolerated, fewer DDIs; monitor Na (EAN 2019 PMID 30860637))
5. lamotrigine 25 mg PO with SLOW titration → 200–400 mg/day PO BID — Refractory / add-on to first-line (RCT-proven add-on (Zakrzewska Pain 1997 PMID 9415510); slow titration mandatory (SJS/TEN))
6. baclofen 5–10 mg PO TID → 50–80 mg/day PO TID — Refractory / add-on; MS-associated TN (AAN/EFNS Level C (PMID 18716236); useful in MS-TN)
7. gabapentin or pregabalin gabapentin 900–3600 mg/day OR pregabalin 300–600 mg/day (renally adjusted) PO TID / BID — Na-channel blockers not tolerated; renal-hepatic limits (Add-on / alternative; renal dose adjustment (calc.ckd_epi_2021))
8. onabotulinumtoxinA intradermal/submucosal injection (~75 U) into pain territory injection every ~12 weeks — Refractory on medical therapy; surgery declined / awaited (RCT-proven adjunct (Wu PMID 22492424; Zhang PMID 25263254))

Non-pharmacologic actions:
- MRI brain trigeminal protocol in ALL — exclude secondary cause + assess NVC
- EARLY neurosurgical referral when medically refractory OR intolerant — do NOT delay (EAN 2019 PMID 30860637)
- Surgical options counselling: MVD (most durable — 70% pain-free 10 yr, Barker NEJM 1996 PMID 8598865), stereotactic radiosurgery (latency, recurrence), percutaneous rhizotomy (sensory-loss/recurrence trade-offs)
- Secondary TN in MS → route neuro.ms-flare.core.v1 (treat the MS)
- Depression/anxiety/suicidality management — refer psychiatry / safety planning if PHQ-9 Q9 positive
- Nutrition + hydration support; dietitian if weight loss from trigger avoidance
- Avoid sodium valproate in people of childbearing potential; pregnancy planning + specialist co-management
- Patient education — trigger management, drug-holiday concept in remission, rash red-flag (SJS/TEN) STOP-and-call instruction

AVOID / contraindication checks:
- Carbamazepine_HLA_B1502_test_before_use_in_Han_Chinese_SE_Asian_Thai_ancestry_SJS_TEN_risk (EAN 2019 PMID 30860637)
- Carbamazepine_oxcarbazepine_eslicarbazepine_hyponatraemia_monitor_sodium_baseline_and_periodic (EAN 2019 PMID 30860637)
- Carbamazepine_aplastic_anaemia_agranulocytosis_leukopenia_monitor_CBC (AAN/EFNS PMID 18716236)
- Carbamazepine_CYP3A4_autoinduction_and_many_DDIs_review_interactions
- Lamotrigine_MANDATORY_slow_titration_rapid_escalation_causes_SJS_TEN (Zakrzewska PMID 9415510)
- Sodium_valproate_AVOID_in_childbearing_potential_teratogenic_neurodevelopmental (EAN 2019 PMID 30860637)
- Gabapentin_pregabalin_renal_dose_adjustment_per_eGFR (calc.ckd_epi_2021)
- Any_evolving_rash_on_CBZ_OXC_lamotrigine_STOP_drug_urgent_evaluation_SJS_TEN_DRESS
- Acute_crisis_unable_to_eat_drink_admit_for_IV_lidocaine_or_fosphenytoin_with_cardiac_monitoring (EAN 2019 PMID 30860637)
- Medically_refractory_or_intolerant_refer_surgery_EARLY_do_not_delay (EAN 2019 PMID 30860637; Barker NEJM 1996 PMID 8598865)
- Secondary_TN_in_MS_treat_the_MS_route_neuro.ms flare.core.v1

Monitoring

Regimen monitoring:
- sodium baseline and at ~2 weeks then periodic on carbamazepine oxcarbazepine eslicarbazepine (EAN 2019 PMID 30860637)
- LFT baseline and periodic on CBZ OXC eslicarbazepine valproate
- CBC baseline and periodic on carbamazepine (AAN/EFNS PMID 18716236)
- carbamazepine level if non response or toxicity autoinduction lowers levels
- rash surveillance SJS TEN DRESS on CBZ OXC lamotrigine
- pain paroxysm diary frequency intensity trigger burden
- mood and suicidality PHQ9 GAD7 at baseline and follow up TN high suicide risk (NRDP 2024 PMID 38816415)
- weight and hydration status trigger avoidance can cause nutrition compromise
- renal function for gabapentin pregabalin dosing

Setting (outpatient) monitoring:
- Sodium + LFT + CBC baseline, ~2 wk, then periodic on CBZ/OXC
- Carbamazepine level if non-response or toxicity
- Pain-paroxysm diary at each visit
- PHQ-9 / GAD-7 at follow-up; suicide-risk re-screen
- Weight + hydration trend
- Rash surveillance (SJS/TEN/DRESS) — patient-initiated STOP-and-call

Follow-up plan: Titrate to lowest effective dose; attempt drug-holiday in remission; neurosurgery candidacy review; secondary TN → underlying-disease pathway; pregnancy planning; longitudinal mood + nutrition (EAN 2019 PMID 30860637; NRDP 2024 PMID 38816415)
- Close-out criterion: Follow-up cadence + return precautions + surgical pathway set

Monitoring phase: Carbamazepine: Na + LFT + CBC baseline, ~2 wk, then periodic; carbamazepine level if toxicity/non-response; oxcarbazepine Na; lamotrigine/CBZ/OXC rash surveillance (SJS/TEN); pain-paroxysm diary; mood/suicidality; weight/hydration (EAN 2019 PMID 30860637; AAN/EFNS PMID 18716236)

Disposition

Current setting: outpatient — Primary site — ICHD-3/ICOP diagnosis + MANDATORY MRI (exclude secondary, assess NVC); carbamazepine or oxcarbazepine first-line titration with Na/LFT/CBC monitoring; add-on/alternative for partial response; EARLY neurosurgical referral when refractory/intolerant; screen + manage depression/suicidality (EAN 2019 PMID 30860637)

Disposition criteria:
- Continue outpatient titration if pain controlled at acceptable cost (EAN 2019 PMID 30860637)
- Neurosurgery referral placed when refractory / intolerant
- Secondary TN → underlying-disease pathway (MS → neuro.ms-flare.core.v1)

Escalation triggers (move to higher acuity):
- Unable to eat/drink/take oral meds OR dehydration / significant weight loss → ED/admission for IV therapy
- Medically refractory OR intolerant → neurosurgery referral (do not delay)
- Secondary-cause red flags (bilateral / V1 / age <40 / sensory deficit / abnormal reflexes) → urgent MRI
- PHQ-9 Q9 positive / active suicidality → urgent psychiatry + safety planning
- Severe hyponatraemia OR evolving rash on CBZ/OXC/lamotrigine → STOP drug + urgent evaluation
- Age >50 + jaw claudication / visual symptoms → STAT ESR/CRP + steroids (GCA) — never delay

Earlier-Return Triggers

Return-precaution thresholds (watch for):
- [SEVERE] Acute TN crisis — pain so severe the patient cannot eat / drink / take oral medication; dehydration / weight loss (EAN 2019 PMID 30860637)
- [SEVERE] Inadequate pain control on optimised medical therapy OR intolerance of first-line agents — surgical-referral trigger (EAN 2019 PMID 30860637)
- [SEVERE] TN ("suicide disease") — positive suicidality screen (PHQ-9 Q9) or severe depression/anxiety (NRDP 2024 PMID 38816415)

Citations

- EAN 2019 guideline on trigeminal neuralgia (Bendtsen, Eur J Neurol) + AAN-EFNS 2008 (Cruccu) + AAN/EFNS 2008 practice parameter (Gronseth) + ICHD-3 + ICOP 1st ed + Nat Rev Dis Primers 2024 [PMID:30860637](https://pubmed.ncbi.nlm.nih.gov/30860637/)
- Cited evidence (PMID 18721143) [PMID:18721143](https://pubmed.ncbi.nlm.nih.gov/18721143/)
- Cited evidence (PMID 18716236) [PMID:18716236](https://pubmed.ncbi.nlm.nih.gov/18716236/)
- Cited evidence (PMID 29368949) [PMID:29368949](https://pubmed.ncbi.nlm.nih.gov/29368949/)
- Cited evidence (PMID 32103673) [PMID:32103673](https://pubmed.ncbi.nlm.nih.gov/32103673/)

Last reconciled with current guidelines: 2026-05-26.
References
  • EAN 2019 guideline on trigeminal neuralgia (Bendtsen, Eur J Neurol) + AAN-EFNS 2008 (Cruccu) + AAN/EFNS 2008 practice parameter (Gronseth) + ICHD-3 + ICOP 1st ed + Nat Rev Dis Primers 2024 — PMID:30860637
  • Cited evidence (PMID 18721143) — PMID:18721143
  • Cited evidence (PMID 18716236) — PMID:18716236
  • Cited evidence (PMID 29368949) — PMID:29368949
  • Cited evidence (PMID 32103673) — PMID:32103673