ModifiedColorado Rocky Mountain Health PlansPolicy CS129.V

Vagus and External Trigeminal Nerve Stimulation

Clinical coverage policy for implantable and noninvasive vagus nerve stimulation (VNS/tVNS) and external trigeminal nerve stimulation (TNS/eTNS) primarily addressing use for epilepsy and other conditions; applies to Colorado Rocky Mountain Health Plans members except where state-specific policies apply.

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyVagus and External Trigeminal Nerve Stimulation

Policy CodePolicy CS129.V

Change TypeTemplate and documentation updates (some substantive definition updates)

Effective DateDec 1, 2025

Next Review DateN/A

Key ActionObtain prior authorization and submit baseline headache diary and documentation of prior therapies when requesting device-based VNS services.

SourceLink

POLICY UPDATE CHANGES

Removed content/language pertaining to the state of Louisiana.

Updated reference link to reflect the current policy title for Transcranial Magnetic Stimulation for Treating Physical Health Conditions.

Updated list of Medical Records Documentation Used for Reviews and removed 'quality of life assessment with quantifiable measures of date-to-life besides the occurrence of seizures'.

Archived previous policy version CS129.U and consolidated updates in current policy.

2+antiseizure medication trials required before implantable VNS

≥50%responder threshold used in cited studies (seizure reduction)

5,223

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participants in Mao et al. VNS meta-analysis

12/01/2025substantive documentation and definitions updated

Coverage Criteria and Evidence Summary

Implantable VNS — medically necessary

Covered when ALL of the following are met:

Implantable VNS coverage criteria: 1) Medically refractory epileptic seizures with failure of two or more trials of single or combination antiepileptic drug therapy or intolerable side effects of antiepileptic drug therapy; 2) The individual is not a candidate for epilepsy surgery, has failed epilepsy surgery, or refuses epilepsy surgery after Shared Decision Making discussion; 3) No history of left or bilateral cervical vagotomy (FDA contraindication).

From Coverage Rationale section

Indication-specific coverage summaries

Indication-specific evidence and guideline positions summarized below; where evidence is limited, recommendation status is noted.

Epilepsy (resective surgery not viable): When resective epilepsy surgery is not a viable option for individuals with drug-resistant seizures, consider offering vagus nerve stimulation (VNS) as an adjunctive therapy alongside antiseizure medications.

Shared decision-making required per NICE (2022, updated 2025).

Treatment‑Resistant Depression (TRD): Evidence is mixed: registry and long‑term observational studies (e.g., Aaronson 2017) show improved cumulative response and remission rates with adjunctive implanted VNS in severely treatment‑resistant populations; randomized trials (e.g., Conway 2025) did not meet the primary MADRS endpoint though some secondary outcomes favored VNS.

Use limited to individuals with documented treatment resistance; evidence quality variable — consider case‑by‑case review.

Cluster Headache (nVNS): Non‑invasive VNS shows efficacy for episodic cluster headache (eCH) in randomized trials and meta-analysis (ACT1/ACT2, De Coo 2020, Goadsby 2018, Silberstein 2016) but not for chronic cluster headache (cCH); preventive data limited.

Evidence supports acute and some prophylactic use in eCH but not in cCH; consider short trial to identify responders.

Migraine: Evidence for non‑invasive VNS in migraine is mixed: systematic reviews and RCTs report increased ≥50% responder rates for cervical nVNS in some analyses but no consistent reduction in migraine days; auricular/low‑frequency approaches show signal in small studies.

Overall evidence limited by small sample sizes, heterogeneous methods, and adherence concerns — many settings consider investigational/insufficient.

Other conditions: Small or low‑quality studies have investigated VNS/tVNS/TNS for conditions such as Alzheimer’s disease, anxiety, OCD, chronic pain, cardiac indications, asthma, fibromyalgia, stroke rehabilitation, and autoimmune disorders; current evidence is insufficient to establish safety and effectiveness for routine coverage.

Further well‑designed clinical trials required before routine coverage; see exclusions for nonroutine indications.

Coverage considerations: limited/conditional evidence

Coverage stance driven by mixed evidence: some trials show benefit in subgroups or adherent patients, but overall evidence is insufficient or low quality for broad coverage.

Situations with some evidence of benefit: Acute nVNS demonstrated superiority for pain freedom at early timepoints in episodic migraine (Tassorelli 2018) and for episodic cluster headache (ACT1/ACT2 analyses); preventive nVNS trials (PREMIUM) showed benefit in prespecified or post‑hoc analyses among adherent participants and those with aura.

Evidence limited by sham device activity, adherence issues, early trial termination, and small subgroup samples.

Insufficient evidence for routine coverage: Systematic reviews and guideline assessments conclude that evidence is limited in quantity and quality, with heterogeneity in stimulation parameters, outcomes, and controls; for many indications (migraine prevention, chronic cluster headache, several nonneurologic indications) data do not establish consistent benefit.

NICE and other bodies recommend special arrangements or research use in some indications rather than routine adoption.

Summary of evidence-based stances

Documented evidence and guideline statements from selected sources in this section

TNS for Major Depressive Disorder (Generoso et al.): A randomized, double‑blind, sham‑controlled phase II trial (n=24) reported a 36.15% mean reduction in HDRS‑17 in the active TNS group after a 10‑day protocol with sustained improvement at one month; authors noted small sample size and limited long‑term follow‑up.

Promising but limited evidence; not sufficient alone for routine coverage decisions.

eTNS for ADHD (AAP guideline): The American Academy of Pediatrics states external trigeminal nerve stimulation (eTNS) cannot be recommended for ADHD because supporting evidence is sparse and does not approach the strength of evidence for established treatments.

Guideline explicitly does not support eTNS for ADHD.

Transcutaneous supraorbital stimulation for migraine (NICE): NICE indicates evidence on safety is adequate and for acute migraine evidence is adequate but recommends use only with special arrangements for clinical governance, consent, and audit or research; evidence for prevention is inadequate and should be used in research only.

Transcutaneous (non‑implantable) vagus nerve stimulation (tVNS/nVNS) and external/transcutaneous trigeminal nerve stimulation (TNS/eTNS) devices are not considered proven for routine coverage because the published literature contains study limitations, small sample sizes, heterogeneous stimulation parameters, and insufficient long‑term outcome data. The policy identifies these device classes as having insufficient evidence of efficacy and safety for preventing or treating the majority of indications and therefore lists them as unproven and not medically necessary for routine use.

For migraine and other headache disorders, published trials and systematic reviews report mixed results and methodological limitations; the policy states that larger, higher‑quality studies are needed to establish safety, efficacy, and long‑term outcomes before these nonimplantable devices would be considered established for routine clinical use.

Because of these evidence gaps, requests for nonimplantable VNS or external TNS devices used outside of defined research or special‑arrangement programs may be denied as unsupported by sufficient clinical evidence.

Implantable vagus nerve stimulation is covered as medically necessary for the specified epilepsy indication described in the policy; however, the policy explicitly states that implantable VNS is unproven and not medically necessary for treating all other conditions beyond that epilepsy indication due to insufficient evidence of efficacy.

The policy lists multiple other conditions for which VNS has been investigated but is not established as effective. These include, but are not limited to: Alzheimer's disease, anxiety disorders, autism spectrum disorder, obsessive‑compulsive disorder, chronic pain syndromes, heart failure, fibromyalgia, sleep disorders, Tourette syndrome, depression, cluster headaches, migraines, and upper‑limb stroke impairment.

The document emphasizes that because many studies are small, uncontrolled, or otherwise limited, there is currently insufficient evidence to conclude that VNS is safe and effective for these indications and that further clinical trials are needed before routine coverage.

For noninvasive vagus nerve stimulation (tVNS/nVNS) the policy states there is insufficient evidence to support routine use across many indications due to study limitations; larger, better‑designed trials with consistent stimulation parameters and longer follow‑up are needed.

Similarly, external or transcutaneous trigeminal nerve stimulation (TNS/eTNS) is described as having inadequate evidence for most indications; the policy summarizes systematic reviews and single‑site trials showing promising signals in some settings but concludes evidence is not yet definitive to support routine coverage.

The American Academy of Pediatrics guideline states that external trigeminal nerve stimulation (eTNS) cannot be recommended as a treatment for ADHD because the supporting evidence is sparse and does not approach the strength of evidence for established medication and behavioral treatments.

The policy aligns with this guideline‑based exclusion for eTNS in ADHD and notes that eTNS is unsupported for that indication in routine clinical practice.

Coverage determinations in this policy are subject to applicable federal, state, and contractual benefit requirements. Where those requirements differ from the policy, the federal, state, or contractual terms govern; providers should verify plan‑specific coverage rules and prior authorization criteria before proceeding.

External/transcutaneous trigeminal nerve stimulation devices are listed as unproven and not medically necessary for preventing or treating the conditions detailed in the policy, including but not limited to ADHD, depression, epilepsy, and headache, because of insufficient and low‑quality evidence.

The policy references systematic reviews and guideline statements that conclude larger, higher‑quality studies are required before TNS/eTNS can be considered established for routine clinical use.

The policy explicitly notes that implantable VNS is unproven and not medically necessary for non‑epilepsy conditions and provides a representative list of those conditions (see policy), reflecting the limited and inconclusive evidence base outside the established epilepsy indication.

Transcutaneous (non‑implantable) vagus nerve stimulation is characterized in the policy as lacking sufficient evidence of safety and efficacy for many indications, including but not limited to migraine, depression, epilepsy, cardiac arrhythmias, and pain syndromes. The document repeatedly emphasizes the need for larger, well‑designed randomized trials and standardized stimulation protocols to establish benefit.

The policy notes investigational activity for a broad range of other conditions—such as atrial fibrillation, premature ventricular contractions (PVCs), heart failure, impaired glucose tolerance, tinnitus, and stroke rehabilitation—but states that current studies are limited by small sample sizes, heterogenous designs, and short follow‑up, leaving evidence insufficient to support routine use.

Across these cardiac, metabolic, and rehabilitation areas the policy calls for additional clinical trials before VNS or tVNS/TNS approaches could be recommended for standard coverage.

The American Academy of Pediatrics' guidance that eTNS cannot be recommended for ADHD is specifically referenced in the policy; the policy statement aligns with this guideline and treats eTNS for ADHD as unsupported by robust evidence.

Consequently, the policy would not support routine coverage of eTNS for ADHD outside of well‑designed research or guideline‑defined special arrangements.

Within the excerpt provided there are no separate explicit entries labeled as formal 'Not Medically Necessary' determinations for every listed condition; the policy text indicates prior revisions removed certain documentation expectations and updated supporting sections, while retaining the substantive evidence‑based exclusions and insufficiency statements reflected elsewhere in the document.

Applicable Codes and Coding Notes

Applicable CPT and supply codesmixed

61885	Insertion or replacement of cranial neurostimulator pulse generator or receiver; with connection to a single electrode array.
61886	Insertion or replacement of cranial neurostimulator pulse generator or receiver; with connection to 2 or more electrode arrays.
64553	Percutaneous implantation of neurostimulator electrode array; cranial nerve.
64568	Open implantation of cranial nerve (e.g., vagus nerve) neurostimulator electrode array and pulse generator.
64570	Removal of cranial nerve (e.g., vagus nerve) neurostimulator electrode array and pulse generator.
A4541	Monthly supplies for use of device coded at E0733.

Applicable HCPCS and L-codesmixed

E0733	Transcutaneous electrical nerve stimulator for electrical stimulation of the trigeminal nerve.
E0735	Noninvasive vagus nerve stimulator.
E0770	Functional electrical stimulator, transcutaneous stimulation of nerve and/or muscle groups, any type, complete system, not otherwise specified.
E1399	Durable medical equipment, miscellaneous.
L8679	Implantable neurostimulator, pulse generator, any type.
L8680	Implantable neurostimulator electrode, each.
L8682	Implantable neurostimulator radiofrequency receiver.
L8683	Radiofrequency transmitter (external) for use with implantable neurostimulator radiofrequency receiver.
L8685	Implantable neurostimulator pulse generator, single array, rechargeable, includes extension.
L8686	Implantable neurostimulator pulse generator, single array, nonrechargeable, includes extension.

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Implantable VNS device product codesmixed

LYJ	FDA product code referenced for implantable vagus nerve stimulators (PMA)
MUZ	FDA product code referenced for implantable vagus nerve stimulators (PMA)
QPY	FDA product code referenced for implantable vagus nerve stimulators (PMA)

Transcutaneous VNS device product codesmixed

PKR	FDA product code referenced for transcutaneous (non-implantable) vagus nerve stimulation devices (PMN)
QAK	FDA product code referenced for transcutaneous (non-implantable) vagus nerve stimulation devices (PMN)

External/TNS device product codesmixed

PCC	FDA product code referenced for external or transcutaneous trigeminal nerve stimulation devices (PMN)
QGL	FDA product code referenced for external or transcutaneous trigeminal nerve stimulation devices (PMN)

Adherence thresholds used in cited nVNS trials

Adherence threshold (trials)Trial analyses used adherence cutoffs of ≥67% and ≥66% to define treatment‑adherent subgroups for efficacy assessments.

Source trial (PREMIUM)Post hoc analysis in PREMIUM used ≥67% monthly adherence to identify responders showing significant differences versus sham.

Source trial (Najib et al. 2022)Modified ITT population included participants who completed ≥70 days and were ≥66% adherent with treatment.

Prior Authorization, Documentation, and Denial Triggers

Billing Rule

Codes Referenced for Authorization

The following codes are provided for prior authorization and billing reference. Inclusion does not guarantee coverage; verify member benefits and applicable laws.

Prior authorization typically expected for implantable devices and services billed with listed CPT/HCPCS/L codes
Provide full coding on authorization request — CPT/HCPCS and any applicable L-codes

Prior Authorization

Prior Authorization Considerations for Implanted VNS in TRD

Implantable VNS for treatment‑resistant depression (TRD) may be considered only after multiple adequate prior treatments and when evidence and plan criteria are met; FDA approval alone does not establish coverage.

Background and Clinical Context

The policy's coverage rationale specifies that implantable VNS is proven and medically necessary only for the defined epilepsy indication (with criteria such as failure of ≥2 antiepileptic drug trials and no prior left/bilateral cervical vagotomy). Outside that indication the policy states implantable VNS is unproven and not medically necessary for other conditions.

The policy history notes that template and documentation changes were made in recent revisions (including removal of certain documentation items), but the substantive evidence‑based exclusions for non‑epilepsy uses remain in the policy text.

Definitions and Terminology

Shared Decision Making (definition & context)

DefinitionShared Decision Making is a collaborative process in which a provider/clinician and a patient (including caregivers and family) work together to make healthcare decisions, weighing evidence, provider experience, and the patient’s values and preferences.

Clinical context (epilepsy)NICE (2022, updated 2025) recommends engaging in shared decision‑making with the person with epilepsy and their family/caregivers before proceeding with VNS, outlining potential benefits and risks.

Policy updateDefinition was updated in the 12/01/2025 policy revision to reflect current wording and supporting information.

nVNS / transcutaneous VNS — definition and evidence

DefinitionnVNS / transcutaneous VNS: non‑implantable (transcutaneous) forms of vagus nerve stimulation delivered externally (cervical or auricular) for acute or preventive use.

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyVagus and External Trigeminal Nerve Stimulation

Policy CodePolicy CS129.V

Change TypeTemplate and documentation updates (some substantive definition updates)

Effective DateDec 1, 2025

Next Review DateN/A

Key ActionObtain prior authorization and submit baseline headache diary and documentation of prior therapies when requesting device-based VNS services.

SourceLink

On This Page

Conditional/limited recommendation per NICE (IPG740, 2022).

Consider VNS in TRD studied as adjunctive after ≥4 prior depression treatments (registry populations typically had failure of 4+ treatments, including ECT)
Prior authorization should document prior treatment history, including trials, durations, and responses
Shared decision‑making (SDM) documentation is required prior to offering implantable VNS for TRD

Documentation Required

Prior Authorization: Baseline Diary and Prior Therapies Required

For migraine or headache indications involving noninvasive devices, prior authorization requests must include a baseline headache diary and documentation of prior therapies and adherence. Lack of these documents may delay or result in denial.

Attach a baseline headache/migraine diary (typically 4 weeks) establishing pre‑treatment monthly migraine days
Document prior pharmacologic preventive and acute therapy trials, reasons for discontinuation, and intolerance or contraindications
Document device treatment adherence (e.g., ≥67% or ≥66% adherence thresholds were used in trials)

Note

FDA Informational Note

The FDA has cleared/approved multiple implantable and non‑implantable VNS and trigeminal nerve stimulation devices. FDA marketing status is informational only and does not by itself determine coverage under member benefits.

Refer to CDRH PMA/510(k)/PMN databases for device marketing information (product codes: LYJ, MUZ, QPY for implantable; PKR, QAK for tVNS; PCC, QGL for trigeminal devices)
Access links provided in policy for device details; FDA clearance/approval does not guarantee benefit coverage

Prior Authorization

Prior Authorization Guidance

This policy serves as guidance for interpreting benefit plans and for prior authorization processes, but final coverage determinations must follow federal, state, and contractual plan terms.

Use this policy with specific member plan language; in conflicts, federal/state/contractual requirements govern
UnitedHealthcare (payer) may use third‑party criteria (e.g., InterQual) and reserves right to modify policies

Denial Risk

Denial Triggers for Implantable VNS

Denial of implantable VNS requests may occur when required clinical criteria are not met, including insufficient prior antiepileptic drug trials or contraindications.

Deny if individual has not failed ≥2 adequate trials of antiepileptic drug therapy for medically refractory epilepsy
Deny if there is a history of left or bilateral cervical vagotomy (contraindication)
Deny if individual is a candidate for resective epilepsy surgery and has not documented refusal or failed surgery after SDM

Denial Risk

Insufficient Evidence for Transcutaneous VNS and eTNS

Transcutaneous (non‑implantable) vagus nerve stimulation and certain external trigeminal nerve stimulation indications lack sufficient evidence for many uses; prior authorization may be denied when submitted for unsupported indications.

Requests for tVNS for indications without adequate evidence (e.g., many non‑epilepsy uses) may be considered experimental and denied
eTNS is not recommended for ADHD by AAP — coverage for ADHD indications is unsupported

Denial Risk

Insufficient Evidence May Lead to Denial

Insufficient or low‑quality evidence for noninvasive neuromodulation in certain indications may lead to claim denial when clinical benefit is not established by the literature or plan criteria.

Denials may result for nVNS or eTNS when trials show inconsistent benefit, small sample sizes, or adherence‑dependent effects
Provide supporting evidence and rationale when requesting coverage outside well‑established indications

Documentation Required

NICE Conditional Use Arrangements

Certain noninvasive trigeminal stimulation procedures may be allowed only with special arrangements for clinical governance, consent, audit, or research, per NICE guidance.

For acute treatment, NICE allows use under special arrangements; for prevention, use is recommended only in research contexts
Documentation of consent, clinical governance, audit plans, or research enrollment should be included with authorization requests when applicable

Documentation Required

Compliance with Plan‑Specific Requirements

Ensure all documentation follows plan‑specific requirements; medical records may be required to assess criteria and do not guarantee coverage. In event of conflict, federal/state/contractual requirements govern.

Include medical records, device trial data, diaries, SDM notes, prior therapy documentation, and device coding on requests
Coverage determinations must comply with applicable federal, state, and contractual plan terms

Documentation Required

Shared Decision‑Making for Epilepsy VNS

For epilepsy, document a shared decision‑making discussion with the patient and caregivers (when appropriate) outlining benefits, risks, and alternatives prior to offering implanted VNS.

Document SDM discussion and the patient’s informed choice in the medical record and attach to authorization request
If surgery was an option and refused, document that refusal following SDM

Documentation Required

Baseline Headache Diary and Adherence Documentation

Clinical trial protocols used baseline diaries and required treatment adherence thresholds; prior authorization requests should mirror these operational expectations where relevant.

Attach a 4‑week baseline headache/migraine diary used to establish monthly migraine days
Document device use/adherence (e.g., ≥66–67% adherence thresholds cited in trials) to support effectiveness claims

Note

FDA Device Reference Documentation

Provide FDA device reference information where available to support device identity and regulatory status; URLs to CDRH databases are provided in policy for verification.

Include device make/model and, if known, PMA/510(k)/PMN identifiers or product codes on authorization requests
Policy lists product codes and links to CDRH PMA and PMN/510(k) databases for device look‑ups

Step Therapy

Consider Prior Pharmacotherapy Before Neuromodulation

Consider adequate pharmacotherapy trials before neuromodulation; for epilepsy, require failure of two or more appropriate antiepileptic drug trials; for migraine consider prior preventive pharmacotherapy unless contraindicated or intolerant.

Document specific medications, doses, durations, and reasons for discontinuation or intolerance
For depression/TRD, document prior antidepressant trials and other interventions (e.g., ECT) as appropriate to TRD definitions

Evidence summaryEvidence is mixed/limited: some RCTs and systematic reviews report efficacy signals for episodic cluster headache and certain migraine outcomes, but overall study size, heterogeneity, sham activity, and adherence limit conclusions.

Regulatory noteDevices for transcutaneous VNS are listed in FDA PMN/clearance records (see product codes PKR, QAK).

Adjunctive (implantable) VNS for treatment‑resistant depression

DefinitionAdjunctive VNS in TRD: surgically implanted vagus nerve stimulation used in addition to treatment‑as‑usual for individuals with chronic or treatment‑resistant depression after multiple prior treatment failures.

Evidence summaryLong‑term registry data (e.g., Aaronson et al. 2017) show higher cumulative response and remission rates with adjunctive implanted VNS versus treatment‑as‑usual in severely treatment‑resistant populations, but randomized evidence has limitations.

Clinical implicationUse generally considered for individuals with documented treatment resistance; prior therapies and rationale should be documented for authorization review.

nVNS (noninvasive vagus nerve stimulation)

DefinitionnVNS: noninvasive vagus nerve stimulation devices (external) such as gammaCore that deliver cervical or auricular stimulation intended for acute or preventive headache treatment.

Clinical notesMulticenter trials (e.g., PREMIUM) and systematic reviews report mixed results; subgroup and adherent participant analyses have demonstrated treatment effects not seen in ITT populations.

Common device examplegammaCore is cited as the nVNS device evaluated in several trials (PREMIUM, Tassorelli 2018).

eTNS / TNS (external/transcutaneous trigeminal nerve stimulation)

DefinitioneTNS / TNS: external or transcutaneous trigeminal nerve stimulation devices (forehead or auricular stimulators) targeting trigeminal sensory branches for migraine, epilepsy, ADHD, and mood disorders.

Evidence summarySystematic reviews and meta‑analyses report potential reductions in migraine attacks, days, and acute medication use, but overall evidence quality is low and treatment protocols vary.

Regulatory/statusEvidence assessments conclude benefits are uncertain and larger, higher‑quality trials are needed to define clinical use.

Implantable Vagus Nerve Stimulator — definition & FDA references

DefinitionImplantable Vagus Nerve Stimulator: a surgically implanted pulse generator and lead system approved by FDA for indications such as epilepsy and treatment‑resistant depression.

FDA product codesReferenced PMA product codes: LYJ, MUZ, QPY for implantable VNS devices (see FDA PMA database).

Regulatory noteFDA approval listings provided for informational purposes; approval alone is not a basis for coverage determinations.

Transcutaneous (Non‑Implantable) Vagus/Trigeminal Nerve Stimulation — definition & FDA codes

DefinitionTranscutaneous (Non‑Implantable) Vagus/Trigeminal Nerve Stimulation: externally applied devices cleared or approved to deliver noninvasive stimulation to vagus or trigeminal nerve branches.

FDA product codesReferenced product codes for transcutaneous VNS: PKR, QAK; for external/TNS devices: PCC, QGL (see FDA PMN/510(k)/PMN databases).

Accessing approvalsLocate device marketing clearance/approval information via the CDRH 510(k) and PMA/PMN databases by product or manufacturer name.

Shared Decision Making — 12/01/2025 definition update

Updated definitionShared Decision Making: the policy definition was updated on 12/01/2025 to reflect current wording and supporting information.

Core meaningA collaborative process between provider and patient (and caregivers) that weighs evidence, clinician experience, and patient values to reach a healthcare decision.

Policy relevanceDocumentation of shared decision‑making is expected when offering VNS for drug‑resistant epilepsy per NICE guidance and policy documentation practices.