Medical PolicyMedical Policy
Policy Num: 08.001.062
Policy Name: Electrotherapy as a treatment modality for Bell's Palsy
Policy ID: [08.001.062] [Ac / LC / M- / P-] [0.00.00]
Last Review: September 25, 2025
Next Review: September 20, 2026
Related Policies: None
| Population Reference No. | Populations | Interventions | Comparators | Outcomes |
|---|---|---|---|---|
| 1 | Individuals:
| Interventions of interest are:
| Comparators of interest are:
| Relevant outcomes include:
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An idiopathic facial nerve palsy, or unilateral facial nerve paresis/paralysis, commonly referred to as Bells’s Palsy, is the most common acute mono-neuropathy disorder of unknown origin affecting a single cranial nerve VII, associated with facial nerve weakness or paralysis. Electrostimulation (electrical stimulation) refers to the application of electrical current through electrodes placed directly on the skin.
For individuals diagnosed with Bell’s palsy who receive electrotherapy as stimulation to the affected facial muscles, the evidence includes systematic reviews. Relevant outcomes are symptoms, quality of life, and treatment-related morbidity. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.
The objective of this evidence review is to determine whether the use of electrotherapy improves the net health outcome in individuals with Idiopathic facial nerve palsy (Bell’s Palsy).
Electrotherapy as a treatment modality for the management of Bell’s Palsy is considered investigational.
Coding
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BlueCard/National Account Issues
State or federal mandates (eg, Federal Employee Program) may dictate that certain U.S. Food and Drug Administration approved devices, drugs, or biologics may not be considered investigational, and thus these devices may be assessed only by their medical necessity.
Benefits are determined by the group contract, member benefit booklet, and/or individual subscriber certificate in effect at the time services were rendered. Benefit products or negotiated coverages may have all or some of the services discussed in this medical policy excluded from their coverage.
There is not a known etiology for the cause of Bell’s Palsy. Evidence suggests that Human herpesvirus 1 is responsible for most of the cases. It is the most common facial weakness/paralysis, associated to a single nerve. It presents as an acute and unilateral nerve paresis (weakness) or paralysis (complete loss of movement). Bell palsy often involves a prodrome of otalgia, and many patients additionally report ipsilateral xerophthalmia, epiphora (tearing), hyperacusis, nasal obstruction, and dysgeusia (taste distortion). The facial asymmetry accompanying Bell palsy may cause dysarthria, oral incompetence, and difficulty expressing emotions nonverbally, resulting in social isolation and emotional distress. 7
Also known as Idiopathic Peripheral Facial Palsy, it is named after Sir Charles Bell [1774 to 1842], who was a Scottish surgeon, neurologist and anatomist.
It is expected that 70-80% of patients recover without treatment, and 95% will recover with prompt pharmacological therapy.
Presentation is sudden and is frequently associated with impairment of taste. Patients may report ipsilateral hyperacusis (sound hypersensitivity) or dry eye. It affects the upper and lower portions of the face. Classic signs are eyebrow sagging, inability to close the eye, disappearance of the nasolabial fold, and drooping at the affected corner of the mouth, which is drawn to the unaffected side. Symptoms are unilateral. Patients will report weakness and numbness on the affected side of the face, a dull ache behind or within the same side ear some days prior, drooling, numbness of the tongue and or a metallic taste in mouth. Facial asymmetry is the most common cause of emergency room visits.7
a. Onset occurs over several hours, up to 72 hrs. Symptoms may present and worse for up to three weeks.
b. Sensory and autonomic dysfunction - Patients may report ipsilateral impaired taste sensation, decreased tearing and/or salivation, dysacusis (ear pain) and hyperacusis (sound sensitivity).
c. Bell’s palsy may occur in men, women, and children but is more common in those 15 to 45 years old; those with diabetes, upper respiratory ailments, or compromised immune systems; or during pregnancy.
d. Atypical presentations of the affected sites or involving portions of the face distinct to the usual pattern of weakness, should prompt further investigation into a differential diagnosis.
Clinical diagnosis is made with the observation of the typical features. | |||
Typical | Timing | Clinical Features | Sensory/Autonomic |
| Presentation of symptoms occurs within three days and its progressive for up to three weeks. Some degree of function occurs within four months. | Unilateral Upper and lower portions of the face Eyebrow sagging Widening of palpebral fissure with sagging g of lower eyelid Flattening or loss of nasolabial fold Drooping of mouth Impaired motor functions on affected side Raising eyebrow Generating forehead wrinkles Closing eye Raising corner of mouth | Ipsilateral impaired taste sensation Ipsilateral decreased tearing and/or salivation Ipsilateral retro-auricular pain and hyperacusis | |
Features that are atypical for Bell's palsy include: | |||
Atypical** | Temporal pattern Sudden onset of symptoms at maximal severity (ie, no progression) Insidious onset of symptoms (eg, over weeks to months) Continued worsening of symptoms beyond three weeks. No improvement in symptoms within four months of onset | Clinical features Bilateral acute facial weakness Additional cranial neuropathies or other neurologic signs Vesicles in ear canal Systemic signs (eg, fever, prominent headache, stiff neck) | |
| **Patients with atypical features require diagnostic evaluation to evaluate for other causes for symptoms. | |||
UpToDate Bell's Palsy: Clinical features and Diagnosis in Adults
Laboratory investigations and imaging are more commonly performed in patients whose diagnosis of Bell palsy is questionable due to the presence of skin or mucosal lesions, other neurological symptoms, insidious paralysis onset, or repeated episodes of paralysis. 7
American Academy of Otolaryngology–Head and Neck Surgery Clinical Guidelines (2013) strongly recommend the following managements steps:
· Oral steroids within 72 hrs of symptom onset for Bell’s palsy patients older than 16 years.
· Optional: Antiviral therapy in addition to oral steroids within 72 hrs of symptom onset.
The AAO–Head and Neck Surgery has no recommendation regarding the effects of physical therapy, surgical decompression, or acupuncture regarding Bell’s palsy patients.
Electrotherapy refers to the therapeutic use of electrical energy and electromagnetic agents in physiotherapy practice. This encompasses various modalities including Transcutaneous Electrical Nerve Stimulation (TENS), therapeutic ultrasound, interferential therapy, neuromuscular electrical stimulation (NMES), shortwave diathermy, and others. Despite decades of long use of electrotherapy modalities, current evidence-based practice has shifted decisively toward active, exercise-based interventions as first-line treatments for most musculoskeletal conditions. Electrotherapy modalities, when used, should complement rather than replace active rehabilitation approaches. As per the article, NICE (UK’s National Institute for Health and Care Excellence) 2021 guidelines for chronic pain management explicitly advises clinicians not to offer TENS, ultrasound, or interferential therapy for chronic primary pain, stating that the evidence does not support their use. A 2019 Cochrane overview examining TENS for chronic pain reviewed nine systematic reviews and found the quality of evidence to be very low. The authors concluded they were "unable to conclude with any confidence that, in people with chronic pain, TENS is harmful, or beneficial for pain control, disability, health-related quality of life, use of pain-relieving medicines, or global impression of change".2
This evidence review was created in August 2025 with searches of the PubMed database. The most recent literature update was performed through August 27, 2025.
Evidence reviews assess clinical evidence to determine whether the use of technology improves the net health outcome. Broadly defined, health outcomes are the length of life, quality of life, and ability to function-including benefits and harms. Every clinical condition has specific outcomes that are important to patients and to managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.
To assess whether the evidence is sufficient to draw conclusions about the net health outcome of a technology, 2 domains are examined: the relevance and the quality and credibility. To be relevant, studies must represent 1 or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The randomized controlled trial (RCT) is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. Randomized controlled trials are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.
The purpose of electrotherapy for individuals who have Bell’s Palsy to provide a treatment option that is an alternative to or an improvement on existing therapies.
The following PICO was used to select literature to inform this review.
The relevant population of interest is individuals with Bell’s Palsy.
The therapy being considered is electrotherapy stimulation.
Comparators of interest include standard of care.
The general outcomes of interest are symptom relief, quality of life, treatment-related morbidity. Specific benefits include quality of life, Bell's palsy has psychological as well as physical effects with facial disfigurement leading to adverse effects on mental health, including anxiety and depression. Specific harm may occur if atypical presentation is not addressed.
Methodologically credible studies were selected using the following principles:
A Bayesian network meta-analysis in 2022 aimed to comprehensively assess the efficacy and safety of all pharmacological and physical treatments (short-term, ≤ 1 month) for patients with acute Bell's palsy. The studies selected consisted of randomized controlled trials comparing two or more regimen in patients with the Bell's palsy to be included in a Bayesian network meta-analysis (NMA). A total of 26 studies representing 3,609 patients having undergone 15 treatments matched the criteria. For facial recovery, acupuncture plus electrical stimulation, steroid plus antiviral plus Kabat treatment, and steroid plus antiviral plus electrical stimulation were the top three options based on analysis of the treatment ranking (probability = 84, 80, and 77%, respectively).
The NMA conducted in this study comprehensively summarized the comparative efficacy and safety of 15 currently available pharmacological and physical therapies for patients with Bell's palsy, including 3,609 patients randomly assigned to corticosteroid, antiviral, acupuncture, electrical stimulation, Kabat treatment, facial exercise, and combined therapy or placebo treatment.
Pharmacotherapy represented by corticosteroids remains the most used regimen for Bell's palsy. Corticosteroids can reduce edema and inflammation of the facial nerve due to their anti-inflammatory mode of action. Antivirals have been used in clinical practice since the isolation of the herpes simplex virus-1 genome from the facial nerve endoneurial fluid of people with Bell's palsy. Steroid and antiviral treatment were noted as a potential positive interaction to reduce the instances of long-term sequelae, including motor synkinesis and crocodile tears, which was consistent with the findings of this study.
Physiotherapy is a potentially good alternative for people with systemic disease or allergies. Kabat treatment, also known as proprioceptive neuromuscular facilitation, consists of the facilitation of the voluntary response of an impaired muscle through the global pattern of an entire muscular section that undergoes resistance. Kabat rehabilitation is particularly indicated to prevent or treat synkinesis due to its focus on motor control of facial movements triggered by different feedback stimulation. Electrical stimulation may improve the facial function of patients with Bell's palsy by using transcutaneous delivered low amplitude, pulsed, electrical current to activate motor nerves innervating weak muscles. However, the genuine role that electrostimulation plays in Bell's palsy treatment is still controversial due to unstandardized parameters of frequency, intensity, pulse duration, treatment time, and several contractions. Facial exercise is an active motion exercise that consists of different facial muscles/motions with variations of speed, amplitude, and force to promote motor control and to avoid altered patterns of movements and overactivity of the unaffected side. The individualization of facial neuromuscular exercise is really important. By inserting needles into specific body regions (acupoints), acupuncture works to stimulate reflexes that activate peripheral nerves and transmit sensory information from the spinal cord to the brain, thus modulating our body physiology. Evidence on acupuncture therapies is still underused in clinical practice.
Steroid plus antiviral plus electrical stimulation had the lowest rate of sequelae but were more likely to lead to mild adverse events. Subgroup analysis revealed that methylprednisolone and acyclovir were likely to be the preferred option. This network meta-analysis indicated that combined therapies, especially steroid plus antiviral plus Kabat treatment, were associated with a better facial function recovery outcome than single therapy. Other physical therapies, such as acupuncture plus electrical stimulation, may be a good alternative for people with systemic disease or allergies. More high-quality trials of physical regimens are needed in the future.
In conclusion, combined therapy, especially steroid plus antiviral plus Kabat treatment, is associated with a better facial function recovery outcome than single therapy. The effect of physical therapy is present, but is usually combined with other drugs, and further trials are needed to provide long-term follow-up data for a complete assessment. Steroid plus antiviral plus electrical stimulation treatment had the lowest rate of sequelae. 12
A 2020 systematic review by Burelo-Peregrino et.al. was conducted to reveal if there was enough evidence to support the use of electrotherapy in the treatment of Bell’s palsy and determine its effectiveness for treating facial peripheral paralysis. The systematic review included studies that analyzed electrotherapy as a therapeutic method for treating individuals with Bell’s palsy, to recover the function of facial muscles. Seven studies involving a total of 131 cases and 113 controls were included in the review. In the studies analyzed, patients received electrotherapy combined with other treatments such as hot-wet facial napkins, massages and muscle reeducation. Although the effect of electrotherapy alone was not evaluated, the use of electrotherapy combined with other treatments produced a significant improvement in the individuals evaluated. Due to the diverse methodologies used and the small number of individuals included in the studies, the efficacy of electrotherapy for treating Bell’s Palsy could not be established.
The results of this systematic review showed that there is an improvement in patients who received electrotherapy, in both phases, acute and chronic. Although the author notes that there is not enough evidence regarding the effectiveness of electrotherapy for treating Bell’s palsy, the results found in this systematic review are oriented towards a positive response to the treatment. It was observed that there are several countries without an up-to-date guide for the long-term treatment of Bell’s palsy. And although it has been stated that receiving electrotherapy in the acute phase of Bell’s palsy is beneficial for patients, and it is highly used in the Mexican clinical practice (for diagnosis and management of Bell’s palsy), there is not enough evidence to support the efficacy of electrotherapy in acute cases. It is necessary to mention that although patients who received electrical stimulation improved their condition in all the studies evaluated, the methodology used in each one was different. In conclusion, Burelo determined that the use of electrotherapy may play an important role in the improvement of patients, but it would be necessary to develop further studies with similar characteristics such as parameters of frequency, intensity, pulse duration, treatment time, number of sessions, number of contractions and even the same area of stimulation, with the purpose of clarifying the genuine role that electrotherapy plays in Bell’s palsy treatment.3
In its last review (2011), the Cochrane Database of Systematic reviews was updated in their effort to evaluate physical therapies for Bell's palsy (idiopathic facial palsy). Randomized or quasi‐randomized controlled trials were selected involving any physical therapy. Participants of any age with a diagnosis of Bell's palsy and all degrees of severity were selected. The outcome measures were: incomplete recovery six months after randomization, motor synkinesis, crocodile tears or facial spasm six months after onset, incomplete recovery after one year and adverse effects attributable to the intervention. For this update to the original review, the search identified 65 potentially relevant articles. Twelve studies met the inclusion criteria (872 participants). Four trials studied the efficacy of electrical stimulation (313 participants), three trials studied exercises (199 participants), and five studies compared or combined some form of physical therapy with acupuncture (360 participants). For most outcomes it was unable to perform meta‐analysis because the interventions and outcomes were not comparable.
For the primary outcome of incomplete recovery after six months, electrostimulation produced no benefit over placebo (moderate quality evidence from one study with 86 participants). Low quality comparisons of electrostimulation with prednisolone (an active treatment) (149 participants), or the addition of electrostimulation to hot packs, massage and facial exercises (22 participants), reported no significant differences. Similarly, a meta‐analysis from two studies, one of three months and the other of six months duration (142 participants) found no statistically significant difference in synkinesis, a complication of Bell's palsy, between participants receiving electrostimulation and controls. A single low-quality study (56 participants), which reported at three months, found worse functional recovery with electrostimulation.
Two trials of facial exercises, both at high risk of bias, found no difference in incomplete recovery at six months when exercises were compared to waiting list controls or conventional therapy. There is evidence from a single small study (34 participants) of moderate quality that exercises are beneficial on measures of facial disability to people with chronic facial palsy when compared with controls and from another single low quality study with 145 people with acute cases treated for three months, in which significantly fewer participants developed facial motor synkinesis after exercise (risk ratio 0.24, 95% CI 0.08 to 0.69). The same study showed statistically significant reduction in time for complete recovery, mainly in more severe cases (47 participants, MD ‐2.10 weeks, 95% CI ‐3.15 to ‐1.05) but this was not a prespecified outcome in this meta-analysis.
Acupuncture studies did not provide useful data as all were short and at high risk of bias. None of the studies included adverse events as an outcome.
In conclusion, there is no high-quality evidence to support significant benefit or harm from any physical therapy for idiopathic facial paralysis. There is low quality evidence that tailored facial exercises can help to improve facial function, mainly for people with moderate paralysis and chronic cases. There is low quality evidence that facial exercise reduces sequelae in acute cases. The suggested effects of tailored facial exercises need to be confirmed with good quality randomized controlled trials. 14
For individuals diagnosed with Bell’s palsy who receive electrotherapy as stimulation to the affected facial muscles, the evidence includes meta-analysis and systematic reviews. Relevant outcomes are symptoms, quality of life, and treatment-related morbidity. The evidence is insufficient to determine that technology results in an improvement in the net health outcome.
| Population Reference No. 1 Policy Statement | [ ] MedicallyNecessary | [X] Investigational |
“Physical therapy should be offered to patients with severe paralysis (House-Brackmann grade V or VI) or persistent paralysis (more than three months)”. Evidence rating: B (inconsistent or limited-quality patient-oriented evidence). 5
“We suggest against the use of electrostimulation. (Weak recommendation: very low confidence in effect estimate.)”
A systematic review identified four studies. Three of the studies (one comparing electrostimulation with massage; one comparing electrostimulation with corticosteroids; and one comparing heat, massage, exercises and electrostimulation with the same treatments excluding electrostimulation) showed no benefit in facial recovery. However, one randomized study showed significantly poorer facial recovery with electrostimulation than with facial exercise. The available very-low-quality evidence provides little support for electrostimulation; in addition, the safety profile of such therapy is unproven, and there is an added cost.6
“No recommendation can be made regarding the effect of physical therapy in Bell's palsy patients. No recommendation based on case series and equilibrium of benefit and harm. No accepted and consistent definition of physical therapy for Bell's palsy was found throughout the literature. Several therapy modalities were discussed, including thermal treatment, electrotherapy, massage, facial exercise, and biofeedback, and most studies combined more than 1 treatment method. Several small studies suggested that physical therapy resulted in some level of improvement in patients experiencing prolonged symptoms. Unfortunately, the therapeutic impact of physical therapy in these case reviews is impossible to separate from spontaneous recovery.”
Electrotherapy for the treatment of facial nerve paralysis, commonly known as Bell's Palsy, is not covered under Medicare because its clinical effectiveness has not been established.9
| Codes | Number | Description |
|---|---|---|
| CPT Codes | 97014 | Application of a modality to 1 or more areas; electrical stimulation (unattended) |
| 97032 | Application of a modality to 1 or more areas; electrical stimulation (manual), each 15 minutes | |
| ICD-10-CM | G51.0 | Bell's palsy |
| Type of Service | Outpatient | |
| Place of Service | Physician Office, Ambulatory |
| Date | Action | Description |
|---|---|---|
| 09/25/2025 | New Policy | Electrotherapy as a treatment modality for the management of Bell’s Palsy is considered investigational. Policy reviewed and approved at the Physicians Advisory Committee. |