Skip to main content
Symptom
dx.
Menu
Clinical Reference
Approaches
I have a symptom
Management
I know the diagnosis
Orthopedic Injuries
Fractures & dislocations
Calculators
Clinical calculators
Practical Skills
ECG
Interpretation guide
POCUS
Bedside ultrasound
Procedures
Step-by-step guides
Resuscitation
ACLS / PALS / NRP
Learn
Blog
Articles & updates
Deep Dive
In-depth clinical reviews
About
Our mission
Symptom
dx.
Clinical Reference
Approaches
I have a symptom
Management
I know the diagnosis
Orthopedic Injuries
Fractures & dislocations
Calculators
Clinical calculators
Practical Skills
ECG
Interpretation guide
POCUS
Bedside ultrasound
Procedures
Step-by-step guides
Resuscitation
ACLS / PALS / NRP
Learn
Blog
Articles & updates
Deep Dive
In-depth clinical reviews
About
Our mission
Get Started
Menu
Clinical Reference
Approaches
I have a symptom
Management
I know the diagnosis
Orthopedic Injuries
Fractures & dislocations
Calculators
Clinical calculators
Practical Skills
ECG
Interpretation guide
POCUS
Bedside ultrasound
Procedures
Step-by-step guides
Resuscitation
ACLS / PALS / NRP
Learn
Blog
Articles & updates
Deep Dive
In-depth clinical reviews
About
Our mission
Loading...
Trigeminal Neuralgia
Cardiovascular Presentations
Abdominal aortic aneurysm
Acute coronary syndrome (NSTEMI)
Acute coronary syndrome (STEMI)
Acute decompensated heart failure
Acute limb ischemia
Acute mesenteric ischemia
Aortic dissection
Aortic stenosis
Atrial fibrillation and flutter
Bradyarrhythmia and heart block
Cardiac arrest
Deep vein thrombosis
Myocarditis
Pericarditis
Pulmonary embolism
Stable angina
Superficial thrombophlebitis
Superior vena cava syndrome
Supraventricular tachycardia
Syncope (cardiogenic)
Unstable angina
Ventricular tachycardia
Respiratory Presentations
Acute bronchitis
Acute respiratory failure
Aspiration pneumonia
Asthma exacerbation
Bronchiolitis
Community-acquired pneumonia
COVID-19 pneumonia
COPD exacerbation
Croup
Croup (laryngotracheobronchitis)
Epiglottitis
Hemothorax
Hospital-acquired pneumonia
Pleural effusion
Pneumothorax (traumatic)
Pulmonary contusion
Spontaneous pneumothorax
Neurological Presentations
Bell's palsy
Benign paroxysmal positional vertigo
Brain abscess
Cauda equina syndrome
Cervical radiculopathy
Concussion (mild traumatic brain injury)
Encephalitis
Guillain-Barré syndrome
Hemorrhagic stroke (intracerebral)
Ischemic stroke
Lumbar radiculopathy
Malignant spinal cord compression
Migraine
Peripheral neuropathy (acute)
Retropharyngeal abscess
Schizophrenia (acute exacerbation)
Seizure (breakthrough:known epilepsy)
Seizure (first-time)
Spinal cord injury
Status epilepticus
Subarachnoid hemorrhage
Tension headache
Transient ischemic attack
Traumatic brain injury (moderate-severe)
Vestibular neuritis
Viral meningitis
Gastrointestinal Presentations
Acute appendicitis
Acute cholecystitis
Acute diverticulitis
Acute pancreatitis
Anal fissure
Choledocholithiasis and cholangitis
Clostridioides difficile colitis
Gastritis
Gastroenteritis (viral and bacterial)
Gastroesophageal reflux disease
Incarcerated or strangulated hernia
Inflammatory bowel disease flare
Large bowel obstruction
Lower GI hemorrhage
Peptic ulcer disease
Perforated viscus
Small bowel obstruction
Upper GI hemorrhage
Genitourinary and Reproductive Presentations
Acute prostatitis
Acute urinary retention
Ectopic pregnancy
Epididymitis
Orchitis
Ovarian torsion
Paraphimosis
Pelvic inflammatory disease
Priapism
Pyelonephritis
Renal laceration
Ruptured ovarian cyst
Testicular torsion
Tubo-ovarian abscess
Urinary tract infection (uncomplicated)
Urolithiasis (renal colic)
Vaginal bleeding (non-pregnant)
Infectious Disease Presentations
Acute sinusitis
Acute tonsillitis
Acute upper respiratory infection
Animal bite
Bacterial meningitis
Cellulitis
Conjunctivitis (bacterial)
Dental abscess
Endocarditis
Febrile neutropenia
Fournier gangrene
Hand-foot-mouth disease
Hepatitis (acute)
Herpes zoster
HIV-related illness
Human bite
Impetigo
Infected diabetic foot ulcer
Infectious mononucleosis
Influenza
Necrotizing fasciitis
Osteomyelitis
Otitis externa
Parasitic infection
Periorbital cellulitis
Peritonsillar abscess
Scabies
Sepsis
Septic arthritis
Spontaneous bacterial peritonitis
Tick-borne illness (Lyme disease)
Tinea infection
Tuberculosis
Viral exanthem
Wound infection
Trauma Presentations
Achilles tendon rupture
ACL and mceniscus tear
Ankle fracture
Ankle sprain
Burn
Calcaneus fracture
Cervical spine fracture
Clavicle fracture
Dental avulsion
Distal radius fracture
Drowning
Elbow fracture and dislocation
Electrical injury
Facial bone fracture
Facial laceration
Femur fracture
Fingertip amputation
Forearm fracture (radius and ulna)
Frostbite
Hand:finger laceration
Heat exhaustion
Heat stroke
Hip fracture
Humeral shaft fracture
Knee dislocation
Knee sprain
Lightning injury
Mandible fracture
Metacarpal fracture
Metatarsal fracture
Muscle strain
Nasal fracture
Non-accidental trauma
Orbital fracture
Patella fracture
Phalanx fracture (finger)
Proximal humerus fracture
Pulmonary contusion
Rib fracture
Rotator cuff tear (acute traumatic)
Scalp laceration
Scaphoid fracture
Shoulder dislocation
Skull fracture
Splenic laceration
Sternal fracture
Supracondylar pediatric fracture
Tendon laceration (hand:wrist)
Thoracic and lumbar spine fracture
Tibia:fibula fracture
Tibial plateau fracture
Toe fracture
Traumatic epistaxis
Traumatic hyphema
Toxicologic Presentations
Acetaminophen toxicity
Alcohol intoxication
Alcohol withdrawal
Anticholinergic toxicity
Anticoagulant overdose
Benzodiazepine overdose
Benzodiazepine:sedative overdose
Beta-blocker and calcium channel blocker toxicity
Carbon monoxide poisoning
Caustic ingestion
Digoxin toxicity
Drug eruption
Foreign body ingestion
Opioid intoxication
Opioid overdose
Opioid withdrawal
Organophosphate
Salicylate toxicity
Serotonin syndrome
Stimulant intoxication (cocaine, methamphetamine)
Tricyclic antidepressant overdose
Psychiatric Presentations
Acute anxiety
Acute psychosis
Agitation:behavioral emergency
Bipolar disorder
Conversion disorder
Major depressive episode
Neuroleptic malignant syndrome
Suicidal ideation and attempt
Musculoskeletal and Rheumatologic Presentations
Acute low back pain (mechanical)
Bursitis
Cervical radiculopathy
Costochondritis
Gout (acute)
Lumbar radiculopathy
Pseudogout
Tendinitis
Dermatology Presentations
Acute eczema (Eczema acute flare)
Allergic contact dermatitis
Erythema multiforme
Henoch-Schönlein purpura
Pressure injury
Psoriasis (acute flare)
Stevens-Johnson syndrome
Toxic epidermal necrolysis
Urticaria (acute)
Environmental and Exposure Presentations
Envenomation (snake, spider, insect)
High-altitude illness
Hypothermia
Hematologic and Oncologic Presentations
Acute chest syndrome
Coagulopathy
Hyperviscosity syndrome
Sickle cell crisis (vaso-occlusive)
Symptomatic anemia
Thrombocytopenia (severe)
Tumor lysis syndrome
Pediatric-Specific Presentations
Bronchiolitis
Croup
Emergency delivery
Febrile seizure
Kawasaki disease
Neonatal jaundice
Neonatal sepsis
Nursemaid's elbow
Pediatric fever 0 to 28 days
Pediatric fever 29 to 60 days
Pediatric fever 61 to 90 days
Pyloric stenosis
Slipped capital femoral epiphysis
Intussusception
Endocrine and Metabolic Presentations
Adrenal crisis
Diabetic ketoacidosis
Hypercalcemia
Hyperosmolar hyperglycemic state
Hypertensive emergency
Hypertensive urgency
Hypoglycemia
Myasthenia gravis crisis
Myxedema coma
Severe hyperkalemia
Severe hyponatremia
Thyroid storm
ENT and Maxillofacial Presentations
Acute laryngitis
Acute otitis media
Acute pharyngitis
Cerumen impaction
Epistaxis (anterior)
Nasal foreign body
Otitis externa
Tympanic membrane perforation
Ophthalmologic Presentations
Acute angle-closure glaucoma
Central retinal artery occlusion
Chemical eye injury
Corneal abrasion
Corneal ulcer
Globe rupture
Ocular foreign body
Orbital cellulitis
Retinal detachment
Obstetric Presentations
Hyperemesis gravidarum
Painful vaginal bleeding in pregnancy
Placenta previa
Placental abruption
Preeclampsia:eclampsia
Preterm labor
Threatened:inevitable:incomplete abortion
Systemic and Miscellaneous Presentations
Anaphylaxis
Angioedema
Cannabis-induced hyperemesis
Trigeminal Neuralgia
POCUS
Procedures
Calculators
Resuscitation
ECG Guide
Back
Clinical Assessment Checklist
Browse categories and answer follow-up questions to refine your symptom profile.
Approach to the Critical Patient
Immediate priorities
Life-threatening presentations requiring immediate action
▶
Severe dehydration from inability to eat or drink
▶
IV fluid resuscitation with normal saline or lactated Ringer
Electrolyte repletion as indicated
NPO status to minimize trigger exposures
New neurologic deficits suggesting secondary cause
▶
Acute focal weakness, diplopia, or ataxia
If new deficits present, emergent neuroimaging required
Neurology or neurosurgery consult trigger
Status neuralgicus — prolonged cluster of attacks unresponsive to oral medication
▶
IV pharmacotherapy required in monitored setting
Analgesia-resistant pain cycle requiring ED-level intervention
Key concepts
TN is a clinical diagnosis based on ICHD-3 criteria
▶
Recurrent unilateral paroxysmal facial pain in trigeminal distribution
Paroxysms lasting less than 2 minutes
Electric shock quality triggered by innocuous stimuli
Triggered paroxysmal pain reported in 91–99% of patients; may be pathognomonic
Classification drives management decisions
▶
Classic TN: neurovascular compression with nerve morphological changes (~75%)
Secondary TN: MS, tumor, AVM (~15%)
Idiopathic TN: no identifiable cause (~10%)
Opioids are ineffective and should be avoided
▶
Associated with need for additional medications in 72% of ED cases
NSAIDs are also generally ineffective for neuralgic pain
PITFALLS
Diagnostic pitfalls
▶
Greater than 80% of TN patients initially seek dental evaluation
▶
Misattribution leads to unnecessary dental procedures
Neurologic diagnosis often delayed years
Sensory loss is not expected in classic TN
▶
Persistent numbness suggests secondary or neuropathic etiology
Warrant urgent MRI if present
Bilateral simultaneous pain is not TN
▶
Bilateral presentation raises concern for MS or systemic disease
History
Pain characterization
Quality and duration
▶
Electric shock, shooting, stabbing, or lancinating quality
▶
Paroxysms typically lasting a fraction of a second to 2 minutes
Individual attacks usually last only seconds
Severity
▶
Often rated 10/10 at peak
Attacks may cluster hundreds of times per day
Refractory period
▶
Brief period after a paroxysm during which pain cannot be retriggered
Nearly pathognomonic when present
Distribution
▶
Unilateral facial pain within trigeminal territory
▶
V2 (maxillary) or V3 (mandibular) most commonly affected
Right side more commonly affected than left
V1 (ophthalmic) involvement alone is atypical; consider alternative diagnoses
Pain does not cross midline simultaneously
▶
Bilateral simultaneous pain requires alternative explanation
Sequential bilateral pain possible but uncommon
Triggers and pattern
Trigger factors
▶
Light touch to face, cheek, lips, or nose
▶
Trigger zones are small and discrete
Discrete trigger zones are nearly pathognomonic
Functional triggers
▶
Talking, chewing, swallowing
Brushing teeth
Shaving or touching the face
Wind or breeze across trigger zone
Absence of triggers suggests alternative diagnosis
Temporal pattern
▶
Episodic clusters over weeks to months
▶
Pain-free remission periods lasting months to years
Remissions become shorter with disease duration
Concomitant continuous background pain
▶
Mild-to-moderate aching or throbbing between paroxysms in subset
Subclassified as TN with concomitant continuous pain
Alarm features
Red flags requiring urgent evaluation
▶
Bilateral simultaneous pain
▶
Concern for MS, systemic disease, or bilateral cranial pathology
Sensory loss or numbness in trigeminal distribution
▶
Suggests secondary TN due to tumor, MS, or neuropathy
Age less than 40 years at onset
▶
Higher suspicion for MS-related TN
First division V1 involvement alone
▶
Less typical for classic TN
Consider alternative diagnoses
Progressive pain without remission periods
▶
Concern for malignancy or infiltrative process
Other neurologic deficits
▶
Weakness, ataxia, visual changes suggest intracranial mass or demyelination
Risk factors and history
Demographic risk factors
▶
Age greater than 50 years
▶
Incidence increases progressively with age
Average onset 50–60 years
Female sex
▶
Higher prevalence than male
Associated conditions
▶
Multiple sclerosis
▶
TN prevalence 2–5% in MS patients
20-fold increased risk compared to general population
OR 8.9 in one population study
Hypertension
▶
Associated with higher TN incidence
Systemic lupus erythematosus
▶
Emerging association (OR 2.84)
Family history
▶
1–2% of patients may have familial link
Rare variants in voltage-gated ion channel genes identified
Prior dental evaluations
▶
History of dental procedures performed for presumed dental pain
▶
Common misdiagnosis pathway
Tooth extractions without relief are a diagnostic clue
Psychiatric history
▶
Depression, anxiety, suicidal ideation
▶
TN profoundly impacts quality of life
Screen at every visit
Physical Exam
Neurologic examination
Cranial nerve assessment
▶
Trigeminal nerve sensory testing
▶
Light touch in V1, V2, V3 distributions bilaterally
Pinprick discrimination
Sensory loss is NOT expected in classic TN
Corneal reflex
▶
Afferent limb carried by ophthalmic branch (V1)
Reduced or absent reflex raises concern for secondary TN
Facial motor function
▶
Masseter and pterygoid muscle strength
Motor branch travels with V3
Trigger zone identification
▶
Light touch in discrete zones can reproduce paroxysm
Do not probe trigger zones unnecessarily
Extended cranial nerve exam
▶
Facial nerve (CN VII) function
▶
Facial weakness suggests mass lesion or MS plaque
Hearing and vestibular function
▶
CN VIII involvement may indicate cerebellopontine angle lesion
Extraocular movements
▶
Diplopia with CN VI palsy suggests elevated ICP or posterior fossa pathology
General and systemic exam
General appearance
▶
Pain behavior during exam
▶
Wincing or guarding with facial touch
Inability to speak during severe attacks
Nutritional and hydration status
▶
Dry mucous membranes from inability to eat or drink
Weight loss from fear of triggering pain
Oropharyngeal exam
▶
Dental pathology
▶
Caries, periodontal disease, cracked teeth
Identify concurrent dental disease to avoid misattribution
Mucosa and tongue
▶
Lesions suggesting herpes zoster or oral pathology
PITFALLS
Examination pitfalls
▶
Neurologic exam is usually normal in classic TN
▶
Normal exam does not exclude diagnosis
Abnormal exam suggests secondary cause
Avoid excessive trigger zone probing
▶
Can precipitate severe prolonged attacks
Brief light touch sufficient to identify trigger zone
Bilateral pain on exam
▶
Requires MRI to exclude MS or bilateral neurovascular compression
Differential Diagnosis
Life-threatening mimics
Intracranial mass
▶
ICD-10 C71.9 (malignant neoplasm of brain, unspecified)
▶
Progressive pain without remission
Associated neurologic deficits
MRI with contrast required
Cerebellopontine angle tumor
▶
Acoustic neuroma or meningioma
May compress trigeminal nerve at root
Hearing loss and CN VII involvement possible
Multiple sclerosis
▶
ICD-10 G35
▶
TN may be the presenting symptom of MS
More common in younger patients
MRI demyelinating plaques at trigeminal root entry zone
Vascular and headache syndromes
Cluster headache
▶
ICD-10 G44.009
▶
Longer attacks 15–180 minutes versus TN seconds to 2 minutes
Orbital or supraorbital location predominantly
Prominent autonomic features: lacrimation, rhinorrhea, ptosis
Restlessness during attack differentiates from TN
SUNCT and SUNA
▶
Short-lasting unilateral neuralgiform headache
▶
Periocular location
Prominent autonomic symptoms
No refractory period unlike TN
Can switch sides
Paroxysmal hemicrania
▶
ICD-10 G44.039
▶
Forehead and eye location
Autonomic symptoms present
Absolute response to indomethacin is diagnostic
Giant cell arteritis
▶
ICD-10 M31.6
▶
Persistent temporal pain with jaw claudication
Age greater than 50 years
Elevated ESR and CRP
Risk of vision loss without treatment
Facial pain mimics
Dental pain
▶
ICD-10 K08.89
▶
Pain localized to specific tooth
Triggered by hot, cold, or biting
Visible oral abnormalities on exam
Glossopharyngeal neuralgia
▶
ICD-10 G52.1
▶
Pain in tongue, pharynx, or deep ear
Triggered by swallowing or coughing not facial touch
Temporomandibular joint disorder
▶
ICD-10 M26.60
▶
Persistent aching near ear and jaw
Bilateral presentation possible
Jaw clicking or limited opening
Postherpetic neuralgia
▶
ICD-10 B02.29
▶
Continuous burning pain rather than paroxysmal
History of herpes zoster in same distribution
Often V1 distribution
Skin changes in affected dermatome
Persistent idiopathic facial pain
▶
ICD-10 G50.1
▶
Dull, aching, constant pain
Poorly localized without trigger zones
No neurologic abnormalities
Trigeminal neuropathy
▶
ICD-10 G50.8
▶
Persistent pain with associated sensory loss
History of trauma, surgery, or autoimmune disease
Laboratory Tests
Baseline metabolic labs
Basic metabolic panel
▶
Sodium level
▶
Carbamazepine causes hyponatremia (SIADH mechanism)
Baseline sodium before initiation
Repeat at 1–2 weeks after starting or dose increase
Renal function
▶
Dosing adjustment for oxcarbazepine
Hydration status assessment in acute exacerbation
Liver function tests
▶
Carbamazepine hepatotoxicity monitoring
Baseline transaminases before initiation
Complete blood count
▶
Baseline before carbamazepine initiation
▶
Rare but serious risk: aplastic anemia and agranulocytosis
Repeat every 3–6 months on therapy
Leukopenia monitoring on chronic therapy
▶
Mild leukopenia common and often not requiring discontinuation
Severe leukopenia warrants drug cessation
Pharmacogenomic and safety testing
HLA-B*15:02 screening
▶
Required before carbamazepine initiation
▶
Patients of Southeast Asian, South Asian, or other at-risk ancestry
Risk of fatal Stevens-Johnson syndrome and toxic epidermal necrolysis
Positive result contraindicates carbamazepine
HLA-A*31:01 testing
▶
Associated with hypersensitivity in European, Korean, and Japanese populations
Risk of drug reaction with eosinophilia and systemic symptoms (DRESS)
Carbamazepine serum level
▶
Target range 17–51 mmol/l (4–12 mcg/mL) for seizure dosing
▶
TN often controlled at lower levels
Toxicity monitoring: dizziness, diplopia, ataxia at supratherapeutic levels
Check if toxicity suspected or poor response
Inflammatory and autoimmune markers
Inflammatory screen for secondary TN
▶
ESR and CRP
▶
Giant cell arteritis exclusion when temporal pain in older adult
MS-associated inflammatory activity assessment
ANA and anti-dsDNA when SLE suspected
▶
SLE associated with TN (OR 2.84)
Anti-phospholipid antibodies if vascular etiology considered
Vitamin B12 and folate
▶
Nutritional assessment in dehydrated patients
▶
Weight loss and reduced oral intake common in severe TN
Deficiency can contribute to neuropathy
Diagnostic Tests
Scoring Systems
ICHD-3 diagnostic criteria for TN
▶
Criterion A: at least 3 attacks of unilateral facial pain
▶
Fulfilling criteria B and C
Criterion B: occurring in one or more trigeminal nerve divisions
▶
With no radiation beyond trigeminal distribution
Criterion C: pain with at least 3 of 4 characteristics
▶
Recurring in paroxysmal attacks lasting from a fraction of a second to 2 minutes
Severe intensity
Electric shock, shooting, stabbing, or sharp quality
Precipitated by innocuous stimuli to the affected side of the face
Criterion D: no better accounted for by another diagnosis
TN classification grading (Cruccu et al., Neurology 2016)
▶
Clinically definite TN: fulfills ICHD-3 criteria
▶
Without additional tests
TN with neurovascular compression on MRI
▶
Classic TN confirmed
TN with causative lesion (MS, tumor)
▶
Secondary TN confirmed
Numeric Pain Rating Scale (NRS)
▶
0–10 scale for attack severity
▶
Greater than or equal to 7 considered severe
Tracks response to pharmacotherapy
Guides admission decisions in status neuralgicus
MRI
MRI brain with and without contrast
▶
Indication: all new TN diagnoses
▶
American Family Physician guideline recommendation
EAN guideline recommendation
Identifies secondary causes in approximately 15% of cases
Protocol for TN evaluation
▶
3T MRI preferred over 1.5T for neurovascular detail
FIESTA or CISS sequence (constructive interference steady state)
High-resolution cisternography to visualize trigeminal nerve at REZ
MPRAGE or T1 volumetric for anatomical correlation
Diagnostic yield
▶
Sensitivity for neurovascular compression varies 52–100% depending on protocol
Specificity improved with 3T and dedicated sequences
Systematic review 2026 (Henssen et al.) confirms protocol dependence
Key findings to report
▶
Vascular contact at root entry zone (REZ)
▶
Vessel identification: superior cerebellar artery most common
Morphological nerve changes: displacement, atrophy, or T2 signal change
Demyelinating plaques at pontine REZ
▶
Confirms secondary MS-related TN
Mass lesion in posterior fossa or cerebellopontine angle
▶
Acoustic neuroma, meningioma, epidermoid
AVM or vascular malformation
CT
CT head without contrast
▶
Role in acute TN presentation
▶
Not diagnostic for TN itself
First-line imaging to exclude hemorrhage, mass, or hydrocephalus
Appropriate when neurologic deficits present acutely
Limitations
▶
Cannot visualize neurovascular compression
Inferior soft tissue resolution compared to MRI
Does not replace MRI for TN workup
CT angiography of the head
▶
Vascular mapping for surgical planning
▶
Identifies offending vessels before microvascular decompression
Superior cerebellar artery anatomy for surgical approach
Used as adjunct to MRI in surgical candidates
Not a first-line ED investigation for TN
Ultrasound
Ultrasound role in TN
▶
No established role in primary TN diagnosis
▶
Cannot visualize intracranial trigeminal nerve anatomy
High-frequency ultrasound of superficial trigeminal branches
▶
Investigational use for guided nerve block procedures
Infraorbital and mental nerve identification for injection
Not standard of care but emerging as procedural guide
Temporal artery ultrasound
▶
Indicated when giant cell arteritis is on differential
Halo sign sensitivity 69%, specificity 82% for GCA
Doppler signal loss in affected segment
Disposition
Admission criteria
Indications for hospital admission
▶
Severe exacerbation with inability to eat or drink
▶
Significant dehydration risk
Malnutrition in prolonged attacks
IV hydration and monitoring required
IV pharmacotherapy requirement
▶
IV fosphenytoin administration requires monitored setting
IV lidocaine infusion requires cardiac monitoring
Inadequate response to oral medications in ED
Acute drug titration needs
▶
Refractory cases requiring rapid dose escalation
Monitoring for drug toxicity during initiation
New neurologic deficits
▶
Urgent neuroimaging and specialist workup required
Cannot be safely managed as outpatient
Discharge criteria
Copy
Criteria for safe discharge
▶
Pain adequately controlled with oral medications
▶
NRS score reduced to tolerable level
Patient able to continue prescribed regimen
Tolerating oral intake
▶
No ongoing dehydration risk
Able to swallow medications
Outpatient follow-up arranged
▶
Neurology referral for all new diagnoses
MRI ordered or scheduled if not yet done
Prescription provided with clear titration instructions
Specialist consultation
Consultation triggers
▶
Neurology
▶
All new TN diagnoses for confirmation, MRI interpretation, and classification
EAN guideline recommendation
Outpatient referral acceptable if stable
Neurosurgery
▶
Failure of 2 or more adequate pharmacotherapy trials
Intolerable medication side effects
Patient preference for surgical evaluation
Lancet Neurology guideline recommendation
Dentistry or oral surgery
▶
Dental pathology cannot be excluded on clinical grounds
Ophthalmology
▶
V1 distribution involvement with corneal reflex concern
Treatment
Acute ED management
Immediate pain management in ED
▶
IV fosphenytoin
▶
Achieved satisfactory relief in 64% of ED cases in retrospective series
Requires monitored setting for cardiac rhythm
Administer at rate not exceeding 150 mg/min (phenytoin equivalent)
Limited controlled evidence but supported by clinical experience
IV lidocaine
▶
Effective per clinical experience; requires cardiac monitoring
Dose: 1.5–5 mg/kg IV over 30–60 minutes
Requires monitoring for QT prolongation and CNS toxicity
Reserved for refractory acute exacerbation
Trigger zone lidocaine injection
▶
Provides short-term relief for refractory acute pain
Infraorbital nerve block: 1–2 mL 1–2% lidocaine without epinephrine
Mental nerve block for V3 distribution
IV fluid resuscitation
▶
Normal saline or lactated Ringer for dehydrated patients
Correct electrolyte abnormalities including hyponatremia
Agents to avoid in acute setting
▶
Opioids
▶
Ineffective in safe doses for TN
Associated with need for additional medications in 72% of cases
NSAIDs
▶
Generally ineffective for neuralgic pain
Not recommended in TN management guidelines
First-line pharmacotherapy
Carbamazepine — drug of choice
▶
Initiation and titration
▶
Starting dose: 200 mg twice daily
Titrate by 200 mg per day every few days to effect
Target dose: 400–800 mg per day in most patients
Maximum dose: 1,200 mg per day
Efficacy
▶
NNT approximately 2 for meaningful pain relief
Initial response rate approximately 75%
Efficacy may wane in 50% of patients over 5–10 years
ACEP Level A equivalent recommendation; Class I evidence
Monitoring requirements
▶
CBC and LFTs at baseline and 3–6 months
Sodium level at baseline and 1–2 weeks after initiation
Carbamazepine level if toxicity suspected
Key drug interactions
▶
CYP3A4 inducer — affects oral contraceptives, warfarin, many medications
Counsel patients about contraceptive failure risk
Dose self-adjustment counseling
▶
Patients may self-adjust within prescribed range based on pain severity
Reduce dose during remission periods
Lancet Neurology guideline recommendation
Oxcarbazepine — alternative first-line
▶
Dosing
▶
Starting dose: 150–300 mg twice daily
Titrate to 300–1,800 mg per day in divided doses
Advantages over carbamazepine
▶
Potentially fewer CNS side effects
Less hepatic enzyme induction
Fewer drug-drug interactions
Cautions
▶
High cross-reactivity if carbamazepine allergy present (25–30%)
Hyponatremia risk similar to carbamazepine
Monitor sodium levels
Second-line and adjunctive pharmacotherapy
Lamotrigine
▶
Adjunctive therapy when first-line insufficient
▶
Starting dose: 25 mg daily, titrate slowly over 6–8 weeks
Target dose: 200–400 mg per day
Risk of SJS/TEN with rapid titration; slow escalation mandatory
EAN guideline supported
Gabapentin
▶
Add-on therapy for partial responders
▶
Starting dose: 300 mg three times daily
Titrate to 900–3,600 mg per day in divided doses
Side effects: sedation, dizziness, weight gain
Pregabalin
▶
Alternative to gabapentin
▶
Starting dose: 75 mg twice daily
Target dose: 150–600 mg per day in divided doses
More predictable pharmacokinetics than gabapentin
Baclofen
▶
Adjunctive agent
▶
Starting dose: 5 mg three times daily
Titrate to 10–25 mg three times daily
Particularly useful in MS-related TN
Botulinum toxin type A
▶
For medically refractory TN or intolerance to oral medications
▶
Injection into trigger zones subcutaneously or submucosal
Dose: 25–75 units total per session
Effect onset within days to weeks; duration 3–4 months
EAN guideline Level B recommendation
Surgical treatment
Microvascular decompression (MVD)
▶
Indication
▶
First-line surgical option for classic TN with neurovascular compression on MRI
Medically refractory TN after 2 or more adequate medication trials
Outcomes
▶
62–89% pain-free at 3–11 year follow-up
5-year prospective study: 59% MVD patients pain-free without medication vs 19% medical management alone
Perioperative mortality: 0.3%
Mechanism
▶
Insertion of Teflon sponge between offending vessel and trigeminal nerve
Restores nerve integrity at root entry zone
Percutaneous procedures
▶
Radiofrequency thermocoagulation
▶
Selectively ablates pain-transmitting fibers
Preferred when MRI shows no neurovascular contact
High initial success but higher recurrence than MVD
Balloon compression
▶
Mechanical compression of Gasserian ganglion
Performed under general anesthesia
Preferred for ophthalmic division involvement
Glycerol injection
▶
Chemical ablation of Gasserian ganglion
Can be performed under local anesthesia
Gamma knife radiosurgery
▶
Non-invasive stereotactic radiosurgery
▶
Pain-free in 30–66% at 4–11 years
Delayed onset of effect: weeks to months
Preferred in poor surgical candidates
Destructive mechanism: demyelination of trigeminal root
Special Populations
Pregnancy
TN in pregnancy
▶
Pharmacotherapy safety considerations
▶
Carbamazepine: FDA category D; neural tube defect risk
▶
2–3 fold increased risk of neural tube defects
Folate supplementation 4 mg per day recommended if used
Discuss risk-benefit with multidisciplinary team
Oxcarbazepine: FDA category C; fetal risk data limited
▶
Similar mechanism to carbamazepine; teratogenicity possible
Avoid unless benefit clearly outweighs risk
Lamotrigine: FDA category C; safer profile than carbamazepine
▶
Preferred anticonvulsant if pharmacotherapy necessary in pregnancy
Pharmacokinetics change significantly in pregnancy; dose adjustment required
Gabapentin and pregabalin: limited human safety data
▶
Insufficient evidence to recommend routine use in pregnancy
Non-pharmacologic options
▶
Trigger avoidance as first-line strategy
Nerve blocks with local anesthetics may be used
Multidisciplinary pain team involvement recommended
Surgical referral
▶
MVD can be performed in pregnancy in severe refractory cases
Gamma knife: deferred if possible due to radiation
Neurosurgery consultation for medically refractory cases
Geriatric
Age-related considerations
▶
Pharmacokinetics in older adults
▶
Carbamazepine clearance reduced: risk of toxicity at standard doses
▶
Start at lower dose: 100 mg twice daily and titrate slowly
Increased fall risk from dizziness and ataxia
Increased hyponatremia risk: monitor sodium closely
Oxcarbazepine and geriatric patients
▶
Also associated with hyponatremia; may be more problematic in elderly
Polypharmacy interactions particularly common
Cognitive effects
▶
Carbamazepine causes sedation and cognitive slowing
▶
May exacerbate baseline cognitive impairment
Beers Criteria: use with caution in older adults
Falls risk
▶
Gait disturbance and dizziness with anticonvulsants increase fall risk
▶
Assess baseline fall risk before initiation
Recommend mobility aids if needed
Surgical candidacy in older adults
▶
MVD carries higher anesthetic risk in elderly with comorbidities
▶
Percutaneous procedures preferred in poor surgical candidates
Gamma knife suitable for frail elderly
Comorbidity and nutrition
▶
TN in elderly may accelerate weight loss and nutritional decline
▶
Nutritional assessment at each visit
Consider dietitian referral for severe cases
Pediatrics
Pediatric TN
▶
Epidemiology in children
▶
TN is rare under age 20
▶
When present, secondary causes must be aggressively excluded
MS and structural lesions are disproportionately common in pediatric TN
Diagnostic approach
▶
MRI with and without contrast is mandatory in all pediatric cases
▶
Exclude structural mass, MS plaque, or vascular malformation
Dedicated posterior fossa imaging protocol
Neurology referral required for all pediatric cases
Pharmacotherapy in children
▶
Carbamazepine
▶
Approved for pediatric use (epilepsy dosing used as reference)
Weight-based dosing: 10–20 mg/kg/day in divided doses
Titrate slowly with monitoring of CBC and LFTs
Oxcarbazepine
▶
Approved for children greater than 4 years
Weight-based dosing: 8–10 mg/kg/day titrated to 30–46 mg/kg/day
Gabapentin
▶
Used as adjunctive therapy in pediatric neuropathic pain
Dosing: 5 mg/kg/day increasing to 25–35 mg/kg/day
Surgical options in children
▶
MVD performed in children with neurovascular compression
▶
Good outcomes reported in adolescents
Pediatric neurosurgery referral required
Percutaneous procedures used when MVD not feasible
Background
Epidemiology
Incidence and prevalence
▶
Annual incidence approximately 4–13 per 100,000 population
▶
Increases with age; highest in those greater than 70 years
Average age of onset 50–60 years
Prevalence approximately 0.03–0.3% of the general population
▶
Female predominance; female-to-male ratio approximately 2:1
Right side more commonly affected than left (60% vs 40%)
Disease associations
▶
Multiple sclerosis
▶
TN prevalence 2–5% in MS patients
OR 8.9 compared to general population
Demyelinating plaque at trigeminal REZ in MS-related TN
Hypertension
▶
Associated with increased TN incidence (population data)
Possible mechanism: arterial tortuosity causing neurovascular compression
SLE
▶
OR 2.84 in propensity-matched analysis
Diabetes and hyperlipidemia
▶
Associated at population level in National Inpatient Sample data
Morbidity and quality of life
▶
Depression in 40–80% of TN patients
▶
Anxiety common; suicidal ideation in severe cases
Social isolation from inability to talk, eat, or go outside
Significant occupational impairment
▶
Inability to work during severe exacerbations
Economic burden substantial
Pathophysiology
Neurovascular compression mechanism (classic TN)
▶
Vascular loop contacts trigeminal nerve at root entry zone (REZ)
▶
Superior cerebellar artery most commonly implicated
Anterior inferior cerebellar artery less common
Arterial pulsation causes progressive demyelination of REZ
Focal demyelination consequences
▶
Loss of myelin sheath insulation at REZ
Ectopic impulse generation in hypersensitized axons
Ephaptic transmission: cross-talk between non-nociceptive and nociceptive fibers
Explains why light touch triggers severe pain
Central sensitization
▶
Chronic demyelination leads to central sensitization
▶
Windup phenomenon in trigeminal nucleus caudalis
Wind-up lowers threshold for pain perception
May explain progressive shortening of remission periods
Secondary TN mechanisms
▶
MS-related TN
▶
Demyelinating plaque at pontine trigeminal root entry zone
Mechanism similar to neurovascular compression but immune-mediated
Tumor-related TN
▶
Mass compression of nerve at any point along course
Invasion or infiltration of nerve by malignancy
Ion channel hypothesis
▶
Voltage-gated sodium channel Nav1.7 and Nav1.8 dysregulation
▶
Familial TN linked to VGSC mutations
Carbamazepine and oxcarbazepine block sodium channels
Explains selective efficacy of sodium channel blockers
Therapeutic Considerations
Evidence base for pharmacotherapy
▶
Carbamazepine has highest quality evidence
▶
NNT approximately 2; supported by multiple randomized controlled trials
AAN Practice Parameter Level A recommendation (Gronseth et al., Neurology 2008)
Efficacy may wane over time due to pharmacologic tolerance
Oxcarbazepine evidence level
▶
AAN Level B recommendation (Gronseth et al., Neurology 2008)
Fewer drug interactions; preferred in polypharmacy patients
EAN 2019 guideline recommendations
▶
Carbamazepine and oxcarbazepine as first-line
Lamotrigine, botulinum toxin, and baclofen as second-line
Surgical decision-making framework
▶
Medical management failure defined as inadequate response to 2 or more first-line agents
▶
Or intolerable side effects at therapeutic doses
MVD preferred for classic TN with neurovascular compression on MRI
▶
Best long-term outcomes (59% pain-free without medication at 5 years)
Lancet Neurology 2020 review recommendation
Percutaneous procedures for patients without clear neurovascular compression
▶
Or those with high surgical risk from anesthesia
Gamma knife appropriate for frail patients or patient preference for non-invasive approach
Natural history considerations
▶
Spontaneous remission periods occur
▶
Taper medications during prolonged remissions
Restart at onset of new cluster
Remissions become shorter with disease duration
▶
Early aggressive treatment may not alter natural history
Long-term medication use risks
▶
Carbamazepine: osteoporosis with chronic use (CYP3A4 induction reduces vitamin D)
Monitor bone density in long-term users
Patient Discharge Instructions
copy discharge instructions
Copy
Diagnosis: Trigeminal Neuralgia
▶
You have been diagnosed with trigeminal neuralgia, a condition causing sudden severe electric-shock-like pain in the face
It is caused by a nerve in the face being irritated, most often by a blood vessel pressing on it
This is a neurological condition, not a dental problem
Your medications
▶
Carbamazepine (Tegretol) — take exactly as prescribed
▶
Start at the dose given to you; your doctor will adjust it
You may feel dizzy or unsteady, especially when starting; avoid driving until stable
Take with food to reduce stomach upset
Do not stop your medication suddenly without speaking to your doctor
▶
Stopping abruptly can cause more pain or seizures
If you are prescribed a second medication (oxcarbazepine, lamotrigine, or gabapentin), follow the same instructions
Blood test monitoring
▶
You will need blood tests to check your sodium level, blood count, and liver function
▶
First blood test within 1–2 weeks of starting carbamazepine
Your doctor will tell you the schedule after that
Trigger avoidance
▶
Identify and avoid your personal triggers
▶
Common triggers: gentle face touch, eating, talking, tooth brushing, cold wind
Eat soft foods at room temperature to reduce attack triggering
Use a straw for beverages if swallowing triggers attacks
Adjusting your dose
▶
Your doctor may allow you to adjust your dose based on pain level and side effects
▶
Increase during pain flares (within prescribed range only)
Decrease or stop during pain-free periods after discussion with your doctor
Return to emergency department immediately for
▶
Skin rash of any kind — STOP carbamazepine immediately and go to the ER
▶
Rare but life-threatening: Stevens-Johnson syndrome risk
Inability to eat or drink due to pain
▶
Risk of dangerous dehydration
New numbness, weakness, vision changes, or other neurologic symptoms
▶
May indicate a new problem requiring urgent evaluation
Fever, sore throat, mouth ulcers, or unusual bruising
▶
Possible sign of blood cell disorder from carbamazepine
Severe dizziness, confusion, or inability to walk normally
▶
May indicate medication toxicity
Thoughts of harming yourself
▶
This condition causes significant suffering; help is available
Follow-up
▶
Neurology appointment arranged: follow up within 2–4 weeks
▶
MRI of the brain will be ordered to evaluate the cause
Specialist will guide long-term management and surgical options if needed
Return to your family doctor within 1 week if pain is not controlled
References
Guidelines and key sources
Cruccu G, Di Stefano G, Truini A. Trigeminal Neuralgia. N Engl J Med. 2020.
▶
NEJM review: classification, pathophysiology, management
https://www.nejm.org/doi/full/10.1056/NEJMra1914484
Amaechi O. Trigeminal Neuralgia: Rapid Evidence Review. Am Fam Physician. 2025.
▶
Current evidence-based clinical practice review
https://www.aafp.org/pubs/afp/issues/2025/0500/trigeminal-neuralgia.html
Bendtsen L, Zakrzewska JM, Heinskou TB, et al. Advances in Diagnosis, Classification, Pathophysiology, and Management of Trigeminal Neuralgia. Lancet Neurol. 2020.
▶
Lancet review: classification, ED management, surgical outcomes
https://pubmed.ncbi.nlm.nih.gov/32822636
Gronseth G, Cruccu G, Alksne J, et al. Practice Parameter: Diagnostic Evaluation and Treatment of Trigeminal Neuralgia. Neurology. 2008.
▶
AAN/EFNS evidence-based practice parameter
https://doi.org/10.1212/01.wnl.0000326598.83183.04
Bendtsen L, Zakrzewska JM, Abbott J, et al. European Academy of Neurology Guideline on Trigeminal Neuralgia. Eur J Neurol. 2019.
▶
EAN guideline: pharmacotherapy and surgical recommendations
https://doi.org/10.1111/ene.13950
Pinto MJ, Gomes A, Pinto M, Abreu P, Costa A. Treatment of Acute Exacerbations of Trigeminal Neuralgia in the Emergency Department. Headache. 2022.
▶
Retrospective case series: IV fosphenytoin 64% efficacy in ED
https://pubmed.ncbi.nlm.nih.gov/36005285
Cruccu G, Finnerup NB, Jensen TS, et al. Trigeminal Neuralgia: New Classification and Diagnostic Grading. Neurology. 2016.
▶
ICHD-3 classification grading framework
https://pubmed.ncbi.nlm.nih.gov/27306631
Henssen D, van Grinsven M, Vissers K, van Goethem J. MRI in the Diagnosis of Trigeminal Neuralgia: A Systematic Review. Eur Radiol. 2026.
▶
Protocol dependence and diagnostic accuracy of MRI for TN
https://pubmed.ncbi.nlm.nih.gov/41307659
Worm J, Heinskou TB, Rochat P, et al. Five-Year Prospective Outcomes of Medical Management and MVD in Trigeminal Neuralgia. J Neurol. 2025.
▶
59% MVD pain-free vs 19% medical management at 5 years
https://pubmed.ncbi.nlm.nih.gov/41102594
Tang M, Devarajan A, Huo L, et al. Identifying Associated Comorbidities in Trigeminal Neuralgia. Clin Neurol Neurosurg. 2025.
▶
Comorbidity associations: hypertension, SLE, hyperlipidemia
https://pubmed.ncbi.nlm.nih.gov/40451122
Ashina S, Robertson CE, Srikiatkhachorn A, et al. Trigeminal Neuralgia. Nat Rev Dis Primers. 2024.
▶
Comprehensive disease primer including quality of life data
https://pubmed.ncbi.nlm.nih.gov/38816415
FDA Drug Label: Carbamazepine (Tegretol). Updated 2025-12-16.
▶
HLA-B*15:02 and HLA-A*31:01 screening requirements
SJS/TEN risk in at-risk ancestral populations
https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8d409411-aa9f-4f3a-a52c-fbcb0c3ec053
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.
← Management Protocols
Home
Management Protocols
Trigeminal Neuralgia