Functional Neurological Disorder (FND)¶
VERSION: 1.2 CREATED: January 30, 2026 STATUS: Draft - Pending Review
DIAGNOSIS: Functional Neurological Disorder (FND)
ICD-10: F44.4 (Conversion disorder with motor symptom or deficit), F44.5 (Conversion disorder with seizures or convulsions), F44.6 (Conversion disorder with sensory symptom or deficit), F44.7 (Conversion disorder with mixed symptom presentation), F44.9 (Dissociative and conversion disorder, unspecified)
SYNONYMS: Functional neurological disorder, FND, conversion disorder, functional neurological symptom disorder, functional movement disorder, functional weakness, functional seizures, psychogenic non-epileptic seizures, PNES, psychogenic non-epileptic events, PNEE, dissociative seizures, functional tremor, functional dystonia, functional gait disorder, functional sensory disorder, functional cognitive disorder, medically unexplained neurological symptoms
SCOPE: Diagnosis (positive clinical signs), acute management, and long-term multidisciplinary treatment of FND. Covers functional motor symptoms (weakness, tremor, dystonia, gait disorder, myoclonus, parkinsonism), functional seizures (PNES/dissociative seizures), functional sensory symptoms, and functional cognitive symptoms. Emphasizes POSITIVE diagnosis based on clinical signs (not diagnosis of exclusion). Includes communication strategies, physical rehabilitation, psychological treatment, and pharmacologic management of comorbidities. For epilepsy, see "New Onset Seizure" and "Status Epilepticus" templates. For organic movement disorders, see specific disorder templates.
PRIORITY KEY: STAT = Immediate | URGENT = Within hours | ROUTINE = Standard | EXT = Extended/atypical cases | - = Not applicable to this setting
═══════════════════════════════════════════════════════════ SECTION A: ACTION ITEMS ═══════════════════════════════════════════════════════════
1. LABORATORY WORKUP¶
1A. Essential/Core Labs¶
| Test | Rationale | Target Finding | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|
| CBC with differential (CPT 85025) | Baseline; rule out infection/anemia as contributor | Normal | STAT | STAT | ROUTINE | STAT |
| CMP (BMP + LFTs) (CPT 80053) | Metabolic encephalopathy screen; electrolytes | Normal | STAT | STAT | ROUTINE | STAT |
| TSH (CPT 84443) | Thyroid dysfunction as contributor to neuropsychiatric symptoms | Normal | URGENT | ROUTINE | ROUTINE | URGENT |
| Blood glucose (CPT 82947) | Hypoglycemia as mimic | Normal | STAT | STAT | ROUTINE | STAT |
| Urinalysis (CPT 81003) | UTI/drug screen | Normal | STAT | STAT | ROUTINE | STAT |
| ESR (CPT 85652) | Inflammatory/autoimmune screen | Normal | URGENT | ROUTINE | ROUTINE | URGENT |
| CRP (CPT 86140) | Inflammatory screen | Normal | URGENT | ROUTINE | ROUTINE | URGENT |
| Vitamin B12 (CPT 82607) | B12 deficiency neuropathy/myelopathy as comorbidity | Normal | - | ROUTINE | ROUTINE | - |
| Vitamin D 25-OH (CPT 82306) | Deficiency associated with chronic pain, fatigue | Normal (>30 ng/mL) | - | ROUTINE | ROUTINE | - |
Note: The purpose of labs in FND is NOT to diagnose FND (which is a positive clinical diagnosis) but to rule out contributing metabolic/inflammatory conditions and to document normal results for patient reassurance and medical-legal purposes. Avoid excessive testing (iatrogenic harm from over-investigation reinforces illness behavior).
1B. Extended Workup (Context-Dependent)¶
| Test | Rationale | Target Finding | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|
| Prolactin (15-20 min post-event) (CPT 84146) | If differentiating epileptic vs functional seizures; elevated post-ictal in epileptic seizures | Normal in functional seizures; elevated (>2x baseline) post-epileptic seizure | URGENT | URGENT | - | URGENT |
| Urine drug screen (CPT 80307) | Substance-related symptoms; psychiatric differential | Negative (document for differential) | STAT | STAT | - | STAT |
| ANA (CPT 86235) | If autoimmune concern based on clinical features | Negative | - | ROUTINE | ROUTINE | - |
| Anti-TPO antibodies (CPT 86376) | Hashimoto encephalopathy if cognitive symptoms prominent | Negative | - | ROUTINE | ROUTINE | - |
| Ceruloplasmin, copper (CPT 82390+82525) | Wilson disease if young onset movement disorder | Normal | - | EXT | EXT | - |
| HbA1c (CPT 83036) | Diabetic neuropathy comorbidity | Normal | - | ROUTINE | ROUTINE | - |
Note: Additional labs should be guided by clinical suspicion for comorbid conditions, NOT ordered reflexively. A negative workup does NOT diagnose FND -- FND is diagnosed by POSITIVE clinical signs.
1C. Rare/Specialized¶
| Test | Rationale | Target Finding | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|
| Autoimmune encephalitis antibody panel (serum and CSF) | If acute onset cognitive/behavioral symptoms; consider anti-NMDAR encephalitis mimic in young patients | Negative | - | EXT | EXT | - |
| Paraneoplastic panel | If atypical features suggesting underlying malignancy | Negative | - | EXT | EXT | - |
| Genetic testing for hereditary dystonia (DYT genes) | If functional dystonia features overlap with hereditary dystonia | Negative | - | - | EXT | - |
2. DIAGNOSTIC IMAGING & STUDIES¶
2A. Essential/First-line¶
| Study | Timing | Target Finding | Contraindications | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|
| MRI brain with and without contrast (CPT 70553) | Within 1-2 weeks (not STAT unless acute stroke concern) | Normal; rules out structural pathology; provides reassurance | Standard MRI contraindications | URGENT | ROUTINE | ROUTINE | URGENT |
| Routine EEG (CPT 95816) | If seizure-like events; baseline for comparison | Normal interictal EEG (does not exclude epilepsy but supports functional diagnosis if events captured) | None significant | URGENT | ROUTINE | ROUTINE | URGENT |
| Video-EEG monitoring (prolonged) (CPT 95711-95720) | Gold standard for differentiating epileptic vs functional seizures; capture typical event | Normal EEG during typical clinical event confirms functional seizures (PNES); diagnostic certainty | None significant | - | URGENT | ROUTINE | URGENT |
| CT head without contrast (CPT 70450) | ED triage if acute presentation | Rule out hemorrhage, mass | None significant | STAT | STAT | - | STAT |
Note: Video-EEG monitoring with capture of a habitual event is the GOLD STANDARD for diagnosing functional seizures (PNES). A normal EEG during a typical event definitively confirms functional seizures. However, some frontal lobe seizures may not show surface EEG changes -- clinical correlation essential. For functional motor symptoms, diagnosis is made by clinical examination (positive signs), NOT by imaging.
2B. Extended¶
| Study | Timing | Target Finding | Contraindications | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|
| MRI spine (cervical/thoracic) | If myelopathy symptoms; weakness with upper motor neuron signs | Normal (rules out structural myelopathy) | Standard MRI contraindications | - | ROUTINE | ROUTINE | - |
| EMG/NCS (electromyography/nerve conduction studies) (CPT 95907-95913) | If peripheral neuropathy or myopathy suspected as comorbidity or mimic | Normal or shows functional patterns (intermittent recruitment, give-way pattern) | None significant | - | ROUTINE | ROUTINE | - |
| DaTscan (dopamine transporter SPECT) (CPT 78607) | If differentiating functional parkinsonism from neurodegenerative parkinsonism | Normal in functional parkinsonism; abnormal in PD/MSA/PSP | None significant | - | ROUTINE | ROUTINE | - |
| Ambulatory EEG (CPT 95711) | If events infrequent; outpatient monitoring alternative to inpatient vEEG | Same as vEEG | None significant | - | - | ROUTINE | - |
2C. Rare/Specialized¶
| Study | Timing | Target Finding | Contraindications | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|
| FDG-PET brain | If functional cognitive disorder vs early neurodegeneration | Normal metabolism in functional cognitive disorder; hypometabolism in neurodegeneration | Uncontrolled diabetes | - | - | EXT | - |
| Functional MRI (fMRI) | Research setting only; not standard clinical use | Altered connectivity patterns in FND | Standard MRI contraindications | - | - | EXT | - |
3. TREATMENT¶
3A. Acute/Emergent (Functional Seizures/Events in ED)¶
| Treatment | Route | Indication | Dosing | Contraindications | Monitoring | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|---|---|
| Verbal reassurance and coaching (first-line acute management) | - | Functional seizure/event in progress | N/A :: - :: - :: Use calm, reassuring voice; "I'm going to help you through this"; grounding techniques (name 5 things you can see); do NOT restrain or force oral airway | None | Event duration; response to verbal cues; vital signs | STAT | STAT | ROUTINE | STAT |
| Avoid unnecessary IV benzodiazepines | - | Do NOT treat functional seizures with benzodiazepines (causes respiratory depression without benefit; iatrogenic harm) | N/A :: - :: - :: Withhold IV lorazepam/midazolam/diazepam unless epileptic seizure cannot be excluded | If epileptic seizure cannot be excluded, treat as epileptic | Respiratory status; document clinical features to differentiate | STAT | STAT | - | STAT |
| Nasal ammonia capsule (smelling salts) | INH | Functional unresponsiveness; can help break functional event | 1 capsule :: INH :: PRN :: Break capsule under nose; response (grimace, withdrawal) confirms awareness and supports functional diagnosis | None significant | Response; document | STAT | STAT | - | STAT |
Note: CRITICAL -- Functional seizures (PNES) do NOT respond to antiseizure medications or benzodiazepines. Treating functional seizures with IV benzodiazepines causes unnecessary respiratory depression, intubation, and ICU admission. The most important acute intervention is recognizing the event as functional. Features suggesting functional seizures: eyes closed during event, side-to-side head movement, asynchronous limb movements, waxing-waning course, prolonged duration (>5 min is unusual for epileptic seizures), rapid postictal reorientation, absence of postictal confusion.
3B. Communication and Diagnosis Delivery¶
| Treatment | Route | Indication | Dosing | Contraindications | Monitoring | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|---|---|
| Diagnosis delivery session (structured communication) | - | All FND patients; THE most important therapeutic intervention | N/A :: - :: - :: Explain FND as a REAL neurological condition (not "all in your head"); the nervous system is not functioning correctly, like a "software problem" rather than "hardware problem"; show positive clinical signs to patient; use neurosymptoms.org as patient resource; validate symptoms; express confidence in diagnosis | None | Patient understanding; emotional response; acceptance; therapeutic alliance | STAT | STAT | ROUTINE | STAT |
Note: HOW the diagnosis is communicated is the single most important factor in treatment engagement and outcomes. Key principles: (1) Use the term "Functional Neurological Disorder" -- not "conversion disorder" or "psychogenic"; (2) Explain it as a problem with HOW the nervous system is working, not structural damage; (3) Show the patient their positive clinical signs (Hoover sign, tremor entrainment) as EVIDENCE of the diagnosis; (4) Express confidence; (5) Emphasize treatability; (6) Avoid implying symptoms are fabricated or "all psychological." Direct patients to www.neurosymptoms.org (run by Prof. Jon Stone) for reliable patient information.
3C. Physical Rehabilitation (Core Treatment)¶
| Treatment | Route | Indication | Dosing | Contraindications | Monitoring | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|---|---|
| Specialized FND physiotherapy | - | Functional motor symptoms (weakness, gait disorder, tremor, dystonia) | Outpatient: 1-2 sessions/week x 12-20 weeks :: - :: - :: FND-specialized physiotherapy focusing on movement retraining, distraction techniques, normalizing movement patterns; NOT standard neuro rehab; requires therapist with FND training | Active psychosis; complete lack of engagement | Functional outcome measures (e.g., 10-meter walk test, Berg Balance Scale, SF-36); patient engagement; symptom trajectory | - | ROUTINE | ROUTINE | - |
| Inpatient multidisciplinary FND rehabilitation | - | Severe functional disability not improving with outpatient therapy | 2-5 days per week x 3-5 weeks :: - :: - :: Intensive inpatient program with PT, OT, psychology, neurology; consensus-based approach; goal-oriented | Severe untreated psychiatric comorbidity; active suicidality | Functional outcome measures; daily progress; discharge goals | - | ROUTINE | ROUTINE | - |
| Occupational therapy (FND-focused) | - | ADL difficulties; upper extremity functional symptoms; work/role adaptation | 1-2 sessions/week :: - :: - :: Functional task retraining; graded activity; sensory retraining; workplace modification | Same as physiotherapy | ADL measures; occupational function | - | ROUTINE | ROUTINE | - |
| Speech-language pathology | - | Functional speech/voice disorder (dysphonia, stutter); functional swallow difficulty | 1-2 sessions/week :: - :: - :: Voice retraining; laryngeal relaxation techniques; behavioral strategies | None | Voice assessment; swallow function | - | ROUTINE | ROUTINE | - |
Note: Physiotherapy is the CORE treatment for functional motor symptoms and has the strongest evidence base (Nielsen et al. 2015 RCT). The approach is fundamentally different from standard neuro rehab: focus is on normalizing automatic movement (distraction-based), NOT strengthening exercises. Standard PT that focuses on impairment may reinforce symptom focus and worsen outcomes.
3D. Psychological Treatment¶
| Treatment | Route | Indication | Dosing | Contraindications | Monitoring | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|---|---|
| Cognitive Behavioral Therapy (CBT) -- FND-focused | - | All FND patients; addresses illness beliefs, avoidance, attention to symptoms | 12-20 sessions :: - :: - :: Weekly 50-min sessions; FND-specific CBT model (Goldstein et al. CODES trial for PNES); addresses predisposing, precipitating, and perpetuating factors | Active psychosis; severe cognitive impairment | Seizure/symptom frequency; functional measures; PHQ-9; GAD-7 | - | - | ROUTINE | - |
| EMDR (Eye Movement Desensitization and Reprocessing) | - | FND with trauma history; PTSD comorbidity | 8-12 sessions :: - :: - :: Standard EMDR protocol; process traumatic memories contributing to FND | Active psychosis; dissociative disorder (relative -- requires specialist); active suicidality | PTSD symptom scales; FND symptom frequency | - | - | ROUTINE | - |
| Psychodynamic psychotherapy | - | FND with significant interpersonal/attachment difficulties; insight-oriented patients | Weekly sessions x 6-12 months :: - :: - :: Explore underlying conflicts, attachment patterns, and emotional processing difficulties contributing to FND | Active psychosis; severe personality disorder (relative) | Symptom frequency; functional measures; therapeutic alliance | - | - | EXT | - |
| Mindfulness-based stress reduction (MBSR) | - | FND with anxiety, body hypervigilance, chronic pain | 8-week group program :: - :: - :: Standard MBSR protocol; body scan modified for FND (reduce body hypervigilance) | None significant | Anxiety/stress measures; symptom severity | - | - | ROUTINE | - |
| Group psychoeducation | - | All FND patients; normalize experience; reduce isolation | 6-8 sessions :: - :: - :: Structured group program covering FND education, coping strategies, self-management | None significant | Attendance; patient satisfaction; knowledge | - | - | ROUTINE | - |
3E. Pharmacologic Management of Comorbidities¶
| Treatment | Route | Indication | Dosing | Contraindications | Monitoring | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|---|---|
| Sertraline | PO | Comorbid depression (present in ~50% FND); anxiety | 50 mg :: PO :: daily :: Start 50 mg daily; titrate q2-4wk; max 200 mg/day | Concurrent MAOIs; QTc prolongation | Suicidality (first 8 weeks); serotonin syndrome; QTc | - | ROUTINE | ROUTINE | - |
| Duloxetine | PO | Comorbid depression + chronic pain (dual benefit) | 30 mg :: PO :: daily :: Start 30 mg daily x 1 week; increase to 60 mg daily; max 120 mg/day | Hepatic impairment; concurrent MAOIs; uncontrolled glaucoma | BP; LFTs; serotonin syndrome; discontinuation syndrome | - | ROUTINE | ROUTINE | - |
| Venlafaxine XR | PO | Comorbid depression + anxiety; chronic pain | 37.5 mg :: PO :: daily :: Start 37.5 mg daily x 1 week; titrate q1wk; max 225 mg/day | Uncontrolled hypertension; concurrent MAOIs | BP; HR; discontinuation syndrome (taper slowly) | - | ROUTINE | ROUTINE | - |
| Amitriptyline | PO | Chronic pain; insomnia; migraine prophylaxis (common FND comorbidities) | 10 mg :: PO :: qHS :: Start 10 mg PO qHS; titrate by 10 mg q1-2wk; max 75 mg qHS for pain/insomnia | Cardiac conduction abnormality; recent MI; urinary retention; glaucoma | ECG if dose >50 mg; anticholinergic effects; sedation; orthostatic hypotension | - | ROUTINE | ROUTINE | - |
| Hydroxyzine | PO | Acute anxiety; agitation in ED/inpatient | 25 mg :: PO :: q6h PRN :: 25-50 mg PO q6-8h PRN; max 100 mg/dose | QTc prolongation; severe hepatic impairment | QTc; sedation | URGENT | URGENT | ROUTINE | - |
| Propranolol | PO | Anxiety with somatic symptoms (palpitations, tremor); comorbid migraine | 10 mg :: PO :: BID :: Start 10 mg PO BID; titrate q1wk; max 80 mg BID | Asthma; AV block; bradycardia; decompensated CHF | HR; BP; bronchospasm | - | ROUTINE | ROUTINE | - |
| Melatonin | PO | Insomnia (common FND comorbidity) | 3-10 mg qHS :: PO :: qHS :: 3-10 mg PO qHS | None significant | Sleep quality | - | ROUTINE | ROUTINE | - |
| Trazodone | PO | Insomnia with comorbid depression | 25-100 mg qHS :: PO :: qHS :: 25-100 mg PO qHS | Concurrent MAOIs; QTc prolongation | Orthostatic hypotension; priapism (rare); sedation | - | ROUTINE | ROUTINE | - |
Note: There is NO medication that treats FND directly. Pharmacotherapy targets COMORBIDITIES (depression, anxiety, pain, insomnia) which are present in the majority of FND patients and perpetuate the disorder. CRITICAL: Taper and discontinue anti-seizure medications in patients with confirmed functional seizures (PNES) -- ASMs are ineffective and cause unnecessary side effects. This should be done gradually under neurologist supervision.
3F. Anti-Seizure Medication Taper (Functional Seizures/PNES)¶
| Treatment | Route | Indication | Dosing | Contraindications | Monitoring | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|---|---|
| Gradual ASM taper (levetiracetam, lamotrigine, valproic acid, etc.) | PO | Confirmed functional seizures (PNES) on unnecessary ASMs; taper AFTER definitive vEEG diagnosis | Per drug-specific taper :: PO :: :: Taper each ASM by 25% every 2 weeks; single-drug taper at a time; monitor for breakthrough if comorbid epilepsy not excluded; complete taper over 2-3 months | Comorbid epilepsy (dual diagnosis: ~10-20% of PNES patients also have epilepsy -- do NOT taper in these patients without epilepsy specialist input) | Event frequency; anxiety (taper anxiety is common); confirm no epileptic events | - | - | ROUTINE | - |
4. OTHER RECOMMENDATIONS¶
4A. Referrals & Consults¶
| Recommendation | ED | HOSP | OPD | ICU |
|---|---|---|---|---|
| Neurology (FND specialist if available) for diagnosis confirmation, positive sign demonstration, and diagnosis delivery | STAT | STAT | ROUTINE | STAT |
| Neuropsychiatry or psychiatry with FND experience for comorbidity management and psychological formulation | - | URGENT | ROUTINE | - |
| Physiotherapy (FND-specialized if available) for movement retraining and functional motor rehabilitation | - | ROUTINE | ROUTINE | - |
| Clinical psychology (CBT for FND) for illness beliefs, avoidance, and perpetuating factors | - | ROUTINE | ROUTINE | - |
| Occupational therapy for ADL adaptation and graded return to activity | - | ROUTINE | ROUTINE | - |
| Speech-language pathology if functional voice disorder or functional swallow symptoms | - | ROUTINE | ROUTINE | - |
| Epilepsy monitoring unit for video-EEG if functional seizures suspected (diagnostic confirmation) | - | URGENT | ROUTINE | - |
| Neuropsychology if functional cognitive symptoms for formal testing and differentiation from neurodegenerative cognitive decline | - | - | ROUTINE | - |
| Pain management if chronic pain comorbidity refractory to standard treatment | - | ROUTINE | ROUTINE | - |
| Social work for disability support, vocational rehabilitation, and family education | - | ROUTINE | ROUTINE | - |
| Peer support group for FND (FND Hope, FND Action, local support groups) | - | - | ROUTINE | - |
4B. Patient Instructions¶
| Recommendation | ED | HOSP | OPD |
|---|---|---|---|
| FND is a REAL neurological condition -- your symptoms are genuine and not imagined or fabricated | Y | Y | Y |
| Visit www.neurosymptoms.org for reliable, expert-written information about FND (recommended by leading FND specialists) | Y | Y | Y |
| FND is treatable -- many patients improve significantly with the right treatment (physiotherapy, psychology, self-management) | Y | Y | Y |
| Understanding the diagnosis is the first step in recovery -- ask your neurologist to show you your positive clinical signs | - | Y | Y |
| Avoid excessive medical testing and doctor shopping; this can reinforce symptoms and delay recovery | - | Y | Y |
| Regular physical activity and graded exercise improve outcomes -- avoid complete rest or bed rest | - | Y | Y |
| If you have functional seizures: during an event, try grounding techniques (5 senses exercise); family/friends should NOT restrain you or call 911 unless injury occurs or event lasts >10 minutes | - | Y | Y |
| Manage stress, sleep, and general health -- these factors influence symptom severity | - | Y | Y |
| Engage with recommended physiotherapy and psychology -- these are the evidence-based treatments | - | Y | Y |
| Recovery is often gradual with setbacks -- this is normal and does not mean the diagnosis is wrong | - | Y | Y |
| Return to ED for new symptoms that are clearly different from your usual FND symptoms, such as sudden severe headache, fever, or one-sided weakness with facial droop (new stroke symptoms) | Y | Y | Y |
4C. Lifestyle & Prevention¶
| Recommendation | ED | HOSP | OPD |
|---|---|---|---|
| Regular aerobic exercise (30 min, 5x/week) to improve mood, reduce pain, and support neuroplasticity | - | Y | Y |
| Sleep hygiene: consistent bed/wake times, avoid screens 1 hour before bed, limit caffeine after noon | - | Y | Y |
| Stress management: mindfulness, breathing exercises, journaling, or other relaxation techniques | - | Y | Y |
| Pacing activities to avoid boom-bust cycle (overactivity on good days → crash on bad days) | - | Y | Y |
| Limit alcohol (lowers seizure threshold; interacts with medications; worsens mood/sleep) | - | Y | Y |
| Avoid benzodiazepines for functional seizures (ineffective and potentially harmful) | - | Y | Y |
| Maintain social connections and meaningful activities -- isolation worsens FND | - | Y | Y |
═══════════════════════════════════════════════════════════ SECTION B: REFERENCE (Expand as Needed) ═══════════════════════════════════════════════════════════
5. DIFFERENTIAL DIAGNOSIS¶
| Alternative Diagnosis | Key Distinguishing Features | Tests to Differentiate |
|---|---|---|
| Epileptic seizures | Stereotyped semiology; postictal confusion; tongue bite; incontinence; EEG abnormalities | Video-EEG with event capture (gold standard); prolactin level; semiology analysis |
| Multiple sclerosis | Relapsing-remitting with MRI lesions; positive OCBs; clinical dissemination in time/space | MRI brain/spine; OCBs; McDonald criteria |
| Myasthenia gravis | Fatigable weakness; ptosis; diplopia; positive edrophonium test; positive antibodies | AChR/MuSK antibodies; repetitive nerve stimulation; ice pack test |
| Parkinson disease | Resting tremor; rigidity; bradykinesia; asymmetric onset; progressive course | DaTscan (abnormal in PD, normal in FND); clinical features |
| Dystonia (organic) | Fixed posture (though fixed dystonia is often functional); genetic/secondary causes; task-specificity | DYT genetic testing; clinical features; response to botulinum toxin |
| Stroke/TIA | Sudden onset; arterial territory pattern; MRI DWI restricted diffusion; vascular risk factors | MRI brain (DWI); CT angiography; clinical examination |
| Autoimmune encephalitis (anti-NMDAR) | Psychiatric symptoms + seizures + movement disorder; CSF pleocytosis; antibodies positive | AE antibody panel (serum and CSF); MRI; EEG |
| Spinal cord pathology (myelopathy) | Upper motor neuron signs; sensory level; bowel/bladder involvement; MRI cord lesion | MRI spine; clinical examination pattern |
| Peripheral neuropathy | Length-dependent pattern; EMG/NCS abnormalities; specific etiologies | EMG/NCS; labs (glucose, B12, SPEP) |
| Wilson disease | Young onset; Kayser-Fleischer rings; liver disease; movement disorder | Ceruloplasmin; 24-hour urine copper; slit lamp exam |
| Creutzfeldt-Jakob disease | Rapidly progressive dementia; myoclonus; MRI cortical ribboning; 14-3-3 protein | MRI DWI; RT-QuIC; 14-3-3; EEG (periodic discharges) |
| Malingering / factitious disorder | Intentional symptom production; external motivation (malingering) or sick role (factitious); RARE in clinical practice -- do NOT assume this | No reliable test; clinical judgment; inconsistency with incentives; FND is NOT malingering |
Note: FND frequently COEXISTS with organic neurological disease (comorbid epilepsy in 10-20% of PNES patients; FND after stroke; FND with MS). The presence of organic disease does NOT exclude comorbid FND. Always evaluate for both.
6. MONITORING PARAMETERS¶
| Parameter | Frequency | Target/Threshold | Action if Abnormal | ED | HOSP | OPD | ICU |
|---|---|---|---|---|---|---|---|
| Functional symptom severity (patient self-report scale) | Each visit | Improving over weeks-months | Reassess treatment plan; consider additional modalities; address perpetuating factors | - | ROUTINE | ROUTINE | - |
| Event/seizure diary (frequency, duration, triggers) | Daily (patient-reported); reviewed at each visit | Decreasing frequency | Adjust psychological treatment; review triggers; medication optimization | - | ROUTINE | ROUTINE | - |
| PHQ-9 (depression screening) | Each visit | Score <5 (remission) | Adjust antidepressant; intensify psychology; psychiatric referral | - | ROUTINE | ROUTINE | - |
| GAD-7 (anxiety screening) | Each visit | Score <5 (remission) | Adjust anxiolytic; psychological treatment; relaxation techniques | - | ROUTINE | ROUTINE | - |
| Functional outcome measures (10-meter walk, Berg Balance, SF-36) | Baseline; q4-8 weeks during therapy; at discharge | Improving | Adjust physiotherapy approach; consider intensive rehab | - | ROUTINE | ROUTINE | - |
| Treatment engagement | Each visit | Attending PT, OT, psychology appointments | Explore barriers; motivational interviewing; adjust modalities | - | ROUTINE | ROUTINE | - |
| ASM taper progress (if applicable) | q2-4 weeks during taper | Complete taper without epileptic events | If events occur: reassess with EEG; consider dual diagnosis | - | - | ROUTINE | - |
| Sleep quality (Pittsburgh Sleep Quality Index) | q3 months | Improving; PSQI <5 | Sleep hygiene review; pharmacologic sleep aids | - | - | ROUTINE | - |
| Return to work/school/activities | q1-3 months | Gradual increase in function | Vocational rehab; occupational therapy; graded return plan | - | - | ROUTINE | - |
| Medication side effects | Each visit | No significant adverse effects | Dose adjustment; medication switch | - | ROUTINE | ROUTINE | - |
7. DISPOSITION CRITERIA¶
| Disposition | Criteria |
|---|---|
| Discharge home | Diagnosis communicated; patient understands FND diagnosis; safety ensured; no acute medical concern; outpatient therapy arranged (PT, psychology); family education completed; resources provided (neurosymptoms.org) |
| Admit to floor | Diagnostic uncertainty requiring further evaluation (video-EEG); severe functional disability preventing safe discharge; acute psychiatric comorbidity (suicidality, psychosis); failure to thrive; recurrent ED visits for functional events requiring care coordination |
| Admit to ICU | Generally NOT indicated for FND; consider only if: iatrogenic complications from inappropriate treatment (benzodiazepine-induced respiratory depression); diagnostic uncertainty with concern for status epilepticus |
| Transfer to higher level of care | Video-EEG monitoring not available; FND-specialized rehabilitation program referral; neuropsychiatry not available |
| Inpatient FND rehabilitation | Severe functional disability; failed outpatient therapy; good engagement and motivation; multidisciplinary program available |
| Outpatient follow-up | ALL patients: neurology follow-up within 2-4 weeks; physiotherapy initiation within 1-2 weeks; psychology referral within 1 month; PCP for comorbidity management |
| Readmission criteria | New symptoms DIFFERENT from established FND pattern (evaluate for new neurological disease); acute psychiatric emergency; severe functional deterioration failing outpatient treatment |
8. EVIDENCE & REFERENCES¶
| Recommendation | Evidence Level | Source |
|---|---|---|
| DSM-5 FND diagnostic criteria (positive neurological signs required) | Expert Consensus | American Psychiatric Association. DSM-5. 2013 |
| FND is a positive diagnosis based on clinical signs, not exclusion | Expert Consensus | Stone J et al. J Neurol Neurosurg Psychiatry 2020;91:615-621 |
| Hoover sign sensitivity and specificity for functional weakness | Class II | Stone J et al. J Neurol 2002;249:1468-1474 |
| Video-EEG gold standard for PNES/functional seizure diagnosis | Class II | LaFrance WC et al. Epilepsia 2013;54 Suppl 1:44-52 |
| CODES trial: CBT for dissociative seizures (largest RCT) | Class I (RCT) | Goldstein LH et al. Lancet Psychiatry 2020;7:491-505 |
| Physiotherapy for FND (Nielsen et al. RCT) | Class I (RCT) | Nielsen G et al. J Neurol Neurosurg Psychiatry 2015;86:1113-1119 |
| FND prognosis: ~40% same or worse at follow-up without treatment | Class II | Stone J et al. Brain 2003;126:1692-1698 |
| neurosymptoms.org: validated patient education resource | Expert Consensus | Stone J. Practical Neurology 2014;14:368-379 |
| Diagnosis communication approach ("software not hardware") | Expert Consensus | Stone J et al. J Neurol Neurosurg Psychiatry 2020 |
| Comorbid epilepsy in 10-20% of PNES patients (dual diagnosis) | Class II | Benbadis SR et al. Neurology 2001;57:915-917 |
| Tremor entrainment as positive sign for functional tremor | Class II | Schwingenschuh P et al. Mov Disord 2016;31:1710-1719 |
| DaTscan normal in functional parkinsonism | Class III | Gaig C et al. J Neurol Neurosurg Psychiatry 2012;83:1145-1149 |
| FND-specialized physiotherapy approach | Expert Consensus | Nielsen G et al. Handb Clin Neurol 2016;139:555-569 |
| Anti-seizure medication taper in confirmed PNES | Expert Consensus | LaFrance WC et al. Neurology 2022;98:186-196 |
| Benzodiazepine harm in functional seizures | Class III | Reuber M et al. Epilepsy Behav 2003;4:74-78 |
| Multidisciplinary inpatient FND rehabilitation outcomes | Class III | Saifee TA et al. J Neurol 2012;259:1934-1940 |
| Predictors of FND prognosis | Class II | Gelauff J et al. J Neurol Neurosurg Psychiatry 2019;90:615-623 |
CLINICAL DECISION SUPPORT NOTES¶
Positive Clinical Signs for FND (Diagnosis BY Examination)¶
Functional Weakness: - Hoover sign (most reliable): Hip extension weakness normalizes with contralateral hip flexion against resistance - Collapsing/give-way weakness: Initial strong resistance that suddenly gives way - Co-contraction: Simultaneous antagonist contraction during movement testing - Drift without pronation: Arm drifts down without pronation (organic UMN lesion causes pronation)
Functional Tremor: - Entrainment: Tremor frequency changes to match voluntary tapping in contralateral limb - Distraction: Tremor stops or changes with cognitive distraction - Variability: Frequency and amplitude change significantly over examination - Co-activation sign: Tremor increases with examiner passively holding the limb
Functional Dystonia: - Fixed posture: Typically fixed from onset (organic dystonia usually starts mobile) - Resistance to passive movement: Active resistance that is not seen in organic dystonia - Ankle inversion pattern: Fixed inverted ankle posture (common in FND, rare in organic)
Functional Seizures (PNES): - Eyes closed during event (epileptic seizures: eyes open in ~95%) - Side-to-side head movement (uncommon in epileptic seizures) - Asynchronous limb movements (thrashing vs. rhythmic tonic-clonic) - Waxing-waning intensity (epileptic seizures: stereotyped evolution) - Prolonged duration (>5 min common; epileptic convulsive seizures typically <3 min) - Rapid postictal reorientation (epileptic seizures: prolonged confusion) - Pelvic thrusting (suggestive but not specific) - Crying/vocalization during event (rare in epileptic seizures)
Functional Gait: - Knee buckling without falling (astasia-abasia) - Excessive slowness disproportionate to examination findings - Dragging monoplegic gait with hip externally rotated - Improvement with distraction (e.g., walking backwards or tandem)
Predisposing, Precipitating, and Perpetuating Factors (3Ps Model)¶
| Factor Type | Examples |
|---|---|
| Predisposing | Childhood adversity/trauma; personality traits (perfectionism, alexithymia); prior neurological illness; family illness models; female sex |
| Precipitating | Physical injury/illness (common trigger); surgery; psychological trauma; life stress; panic attack; dissociative episode |
| Perpetuating | Illness beliefs ("I have a brain tumor"); avoidance behaviors; deconditioning; iatrogenic reinforcement (unnecessary tests, incorrect diagnoses); disability/litigation; family accommodation; untreated psychiatric comorbidity |
What NOT to Do in FND¶
| Harmful Approach | Why It's Harmful | Instead Do |
|---|---|---|
| "There's nothing wrong with you" | Invalidating; damages therapeutic alliance | "This is a real condition called FND" |
| "It's all in your head" | Stigmatizing; inaccurate | "Your nervous system isn't working correctly" |
| Excessive testing | Reinforces illness behavior; delays treatment | Targeted testing based on clinical suspicion |
| IV benzodiazepines for functional seizures | Respiratory depression; iatrogenic ICU admission | Verbal coaching; grounding techniques |
| Anti-seizure medications for PNES | Ineffective; unnecessary side effects | Taper ASMs; CBT; physiotherapy |
| "Diagnosis of exclusion" approach | Delays diagnosis; implies doubt | Use positive clinical signs for diagnosis |
| Referring to psychiatry without explanation | Patient feels dismissed | Explain multidisciplinary approach as standard care |
CHANGE LOG¶
v1.2 (January 30, 2026) - Citation verification: removed 13 unverified PubMed links (converted to plain text); retained 3 verified links (Goldstein, Nielsen, Benbadis) and DSM-5 org link - CPT enrichment: added 2 CPT codes (86376, 82390+82525)
v1.1 (January 30, 2026) - Standardized structured dosing format in Section 3E (Pharmacologic Management) - Fixed standard_dose field to contain starting dose only (sertraline, duloxetine, venlafaxine, amitriptyline, hydroxyzine, propranolol) - Added frequency field to all medications
v1.0 (January 30, 2026) - Initial creation - Section 1: 9 core labs (1A), 6 extended (1B), 3 rare (1C) - Section 2: 4 essential imaging/studies (2A), 4 extended (2B), 2 rare (2C) - Section 3: 6 subsections: - 3A: 3 acute/emergent management approaches - 3B: 1 communication/diagnosis delivery - 3C: 4 physical rehabilitation modalities - 3D: 5 psychological treatments - 3E: 8 pharmacologic treatments for comorbidities - 3F: 1 ASM taper protocol - Section 4: 11 referrals (4A), 11 patient instructions (4B), 7 lifestyle recommendations (4C) - Section 5: 12 differential diagnoses - Section 6: 10 monitoring parameters - Section 7: 7 disposition criteria - Section 8: 17 evidence references with PubMed links - Clinical Decision Support Notes: Positive clinical signs by symptom type, 3Ps model, harmful approaches table