Bell's Palsy

Bell's Palsy

1 Overview

Summary and Quick Facts

  • Bell’s palsy involves dysfunction of a nerve that controls facial muscles, resulting in weakness or paralysis of one side, or more rarely both sides, of the face. Most people with Bell’s palsy partially recover without treatment within two to three weeks, achieving full recovery within three or four months.
  • In this protocol, you will learn about the biology of Bell’s palsy and possible triggers. You will learn about innovative and emerging therapies as well as integrative interventions that may help speed recovery and reduce the severity of symptoms.
  • Physicians may use corticosteroids to treat Bell’s palsy as they are helpful in reducing inflammation of the facial nerve and may shorten symptom duration if initiated soon after onset. Given the role of inflammation in Bell’s palsy, natural agents that help manage the inflammatory response, such as curcumin and omega-3 fatty acids from fish oil, may help support a more balanced immune response during viral reactivation in the facial nerve.

Bell’s palsy involves dysfunction of a nerve that controls facial muscles, resulting in weakness or paralysis of one side, or more rarely both sides, of the face. Most people with Bell’s palsy partially recover without treatment within two to three weeks, achieving full recovery within three or four months.

Integrative interventions including methylcobalamin, acetyl-L-carnitine, and omega-3 fatty acids can help improve recovery and protect nerves from inflammatory damage.

Causes and Risk Factors for Bell’s Palsy

  • Herpes simplex virus type 1 (HSV-1) and herpes zoster virus (chickenpox)
  • Commonly affects people ages 15‒50  
  • Diabetes, pregnancy, and lowered immunity increase risk

Signs and Symptoms of Bell’s Palsy

  • One-sided facial paralysis that occurs over a few hours to a few days. This includes a droop to the mouth on the affected side and an inability to frown, close the eye, or produce tears.
  • This can cause the cornea to become dried out which could lead to long-term visual impairment.
  • In most cases, symptoms resolve completely. However, people who do not have some recovery within 21 days have a greater risk of lasting facial muscle weakness.

Note: It is important that a medical professional differentiates Bell’s palsy from stroke. Medical attention should be sought when symptoms of facial paralysis begin to appear irrespective of whether they are thought to be caused by Bell's palsy or stroke.

Diagnosis of Bell’s Palsy

  • Bell’s palsy is a clinical diagnosis based on symptoms as well as history and physical exam findings.
  • Two grading scales are used to quantify the severity of Bell’s palsy: the House-Brackmann Facial Nerve Grading System and the Sunnybrook Facial Grading System.

Conventional Treatment for Bell’s Palsy

  • Corticosteroids are used to reduce inflammation. Artificial tears and ophthalmic ointments can be used to prevent damage to the cornea.
  • Surgery to relieve compression on the facial nerve may be necessary in some cases.

Novel and Emerging Strategies for Bell’s Palsy

  • Infusion therapy consists of corticosteroids mixed in an infusion solution containing dextran and pentoxifylline, which increase blood flow to the facial nerve.
  • Studies have found that laser therapy and hyperbaric oxygen therapy can be helpful for recovery from Bell’s palsy.

Dietary and Lifestyle Interventions

  • A low-arginine/high-lysine diet may help slow the growth of the herpes simplex virus and shorten the duration of Bell’s palsy. Foods low in arginine and high in lysine include dairy products, fish, and chicken.
  • Acupuncture may relieve symptoms of Bell’s palsy, and biofeedback can treat involuntary muscle movements that sometimes occur after incomplete recovery from Bell’s palsy.

Integrative Interventions

  • Methylcobalamin: Methylcobalamin plus a steroid helped patients recover much faster than a steroid alone in a study of subjects who had Bell’s palsy longer than two weeks.
  • Acetyl-L-carnitine: A study of subjects with facial palsy found that supplementing with acetyl-L-carnitine along with methylprednisolone reduced a measure of paralysis by half, whereas it remained the same with methylprednisolone alone.
  • Omega-3 fatty acids: Omega-3 fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) support the creation of different anti-inflammatory compounds that can protect nerves from damage.
  • Niacin: In a series of 74 cases treated with 100‒250 mg of niacin, 73 cases resulted in good facial nerve response within 2‒4 weeks.
  • Anti-viral interventions: Natural agents shown to combat viral infection, including licorice, zinc, lysine, and reishi mushrooms, may be of some benefit for those affected by Bell’s palsy.

2 Introduction

Bell’s palsy is a disorder in which a nerve that controls the facial muscles becomes dysfunctional, resulting in weakness or paralysis of one side, or more rarely, both sides of the face. It often manifests rapidly, such that those affected may rise from bed in the morning with inexplicable one-sided facial weakness or paralysis and fear that they have experienced a stroke (Baugh 2013).

Bell’s palsy is the most common disorder affecting the facial nerve, with more than 60 000 cases diagnosed each year in the United States (Kölln 2009; Zandian 2014; Basic-Kes 2013; NINDS 2012). Bell’s palsy can occur at almost any age and is equally common in men and women, but diabetics have a 4-fold increased risk. Also, the risk triples during pregnancy (especially in the third trimester or first week postpartum) (Tiemstra 2007; Marson 2000; Ronthal 2013a; Zandian 2014; Riga 2012; Kölln 2009).

The core underlying cause responsible for Bell’s palsy is not known with certainty, but evidence indicates that inflammation and reactivation of a dormant viral infection affecting the facial nerve, also called the seventh cranial nerve, appear to be important contributing factors in many cases. Herpes viruses, specifically herpes simplex virus type 1 and herpes zoster virus, which causes chickenpox, are thought to be involved in a substantial proportion of cases (Holland 2004; Zandian 2014).

Physicians may use corticosteroids to treat Bell’s palsy as they are helpful in reducing inflammation of the facial nerve and may shorten symptom duration if initiated soon after onset. Antiviral drugs such as acyclovir are sometimes used for the condition. However, some studies suggest that antiviral drugs do not provide significant benefits when used alone or together with steroids such as prednisolone. Therefore, if there is a benefit with antiviral drugs, the benefit is likely modest at best (Baugh 2013; Ronthal 2013b; Lampert 2012; Sullivan 2007; Holland 2004; Zandian 2014; Gronseth 2012).

Given the role of inflammation in Bell’s palsy, natural agents that help manage the inflammatory response, such as curcumin and omega-3 fatty acids from fish oil, may help support a more balanced immune response during viral reactivation in the facial nerve. In addition, nutrients that support healthy nerve cell function such as vitamin B12 and acetyl-L-carnitine may also confer benefits to those afflicted with Bell’s palsy. For example, vitamin B12 has been shown to improve recovery time of facial nerve function in Bell’s palsy patients compared to those treated with only steroids. Additionally, nutrients that inhibit the herpes viruses may be supportive (Lu 2010; Singer 2008; Kandhare 2012; Kulkarni 2010; Liu 2013; Mezzina 1992; Jalaludin 1995; Kennedy 2010; Fiore 2008; Pompei 1979; Pu 2013; Sekizawa 2001; Nabeshima 2012; Gaby 2006; O’Dell 1990; NINDS 2012; Flodin 1997; Griffith 1987; Ozden 2011; EBSCO CAM Review Board 2011).

In this protocol, you will learn about the biology of Bell’s palsy and possible triggers. You will also learn how to recognize the signs and symptoms of this condition, and how it is diagnosed and conventionally treated. Finally, you will learn about novel and emerging therapies as well as integrative interventions that may help speed recovery and reduce the severity of symptoms.

3 Background

Bell’s palsy is believed to be caused by inflammation of the facial nerve (Mayo Clinic 2012a). The facial nerve controls many of the muscles involved in facial expressions and also carries sensory information from the anterior (frontal) two-thirds of the tongue (Misulis 2010). In addition, this nerve also helps control the lacrimal glands (responsible for tear production) and submandibular glands (involved in producing saliva) (Kosins 2007; Zandian 2014; Ronthal 2013a).

The facial nerve passes through small canals in the skull along its path to innervate the facial muscles. When a dormant virus reactivates and migrates into the facial nerve, an inflammatory response ensues, leading to swelling and compression of the nerve within these small bony passages. Non-infectious factors, such as autoimmune processes, may also cause inflammation of the facial nerve and contribute to Bell’s palsy (Zandian 2014; Ogawa 1982; Sekiya 1990; Gantz 1983; Kölln 2011).

Most people with Bell’s palsy recover considerably well without treatment within 2 to 3 weeks, achieving full recovery within 3 or 4 months. About 70% of the patients with complete paralysis and up to 94% of the patients with partial paralysis completely recover their facial muscle function, even without treatment. On rare occasions, long-term problems such as facial weakness or involuntary facial movements may arise. Overall, 80-90% of patients have complete recovery within 6 weeks to 3 months. Nevertheless, Bell’s palsy may produce psychologically troubling symptoms such as drooling and abnormal facial appearance; some patients also report changes in hearing in the ear on the affected side, dizziness, abnormal taste sensation, pain or discomfort around the jaw, and difficulty eating or drinking (Taylor 2013; Holland 2004; Baugh 2013; Kölln 2009; Mooney 2013; Zandian 2014; NINDS 2012).

One important consideration is that inability to close the eye on the affected side of the face can cause the cornea to become dried out (A.D.A.M. 2013), which could lead to long-term visual impairment. Thus, it is important to seek proper medical care from a qualified healthcare provider to ensure appropriate precautions are taken. Consulting a physician as soon as symptoms emerge is also important because delayed diagnosis and treatment may increase the likelihood of long-term problems (Taylor 2013; Holland 2004; Baugh 2013; Kölln 2009; Mooney 2013; Ronthal 2013b).

4 Causes and Risk Factors

Bell’s palsy has historically been considered an idiopathic condition (ie, a condition that arises spontaneously or from an obscure or unknown cause), but it is now known to be closely associated with exposure to certain viruses (Ferri 2014; Holland 2004; Ronthal 2013a). The virus most closely associated with Bell’s palsy is herpes simplex virus type 1 (HSV-1). One study found that 11 of 14 patients with Bell’s palsy (79%) had evidence of infection with HSV-1 in the region affected compared to none of the controls (Murakami 1996).

HSV-1 and other members of the herpes family of viruses are notable for having two distinct stages in their life cycles. During the first stage, also known as productive infection, the virus is actively replicating and making new copies of itself. Afterward, the virus is able to go into the second phase, known as latent infection. During this time, copies of the virus that are not actively replicating remain in the sensory neuron and cause no symptoms of infection. However, the virus may become reactivated and give rise to an active infection (Taylor 2002). Several studies suggest the reactivation of latent infection with herpes viruses, including HSV-1 and herpes zoster virus (chickenpox), represents a major initiating factor of Bell’s palsy (Holland 2004). Other infectious agents may be involved in some cases as well, including adenovirus, Coxsackievirus, cytomegalovirus, Epstein-Barr virus, mumps, and rubella (Ferri 2014; Morgan 1992; Zandian 2014).

Some people may have a genetic predisposition for Bell’s palsy as well (Ronthal 2013a). Reports of families with multiple cases of Bell’s palsy among immediate relatives suggest there may be some hereditary aspects of Bell’s palsy (Desanto 1969; Hageman 1990; Clement 2000).

Bell’s palsy can occur at any age, but it most commonly affects people between the ages of 15 and 50 (Monini 2010; Peitersen 2002; Zandian 2014). Diabetes increases the risk of developing Bell’s palsy and is present in 5-10% of people with Bell’s palsy (Zandian 2014; Ronthal 2013a). Pregnancy as well as recent upper respiratory ailments or a weakened immune system can also increase the risk of Bell’s palsy (Baugh 2013; Ferri 2014; Monini 2010).

5 Signs and Symptoms

The classic sign of Bell’s palsy is unilateral facial paralysis that typically occurs over a matter of hours to a few days (Ferri 2014; Ronthal 2013a). The paralysis may be partial (one-third of cases) or total (two-thirds of cases) and affects both the upper and lower facial muscles (Misulis 2010; Ferri 2014). Sometimes both sides of the face may be affected simultaneously, but this is rare; one study found that bilateral simultaneous facial palsy occurred in less than 1% of cases (Kim 2008).

Typically, the facial weakness worsens during the first few days but usually improves thereafter (Holland 2004; Misulis 2010). The forehead will stop furrowing and the corner of the mouth will droop on the affected side. Another feature of Bell’s palsy is an inability to close the eye as a result of the lower eyelid drooping. Attempting to close the eye can cause the eyeball to roll upward, known as Bell’s phenomenon (Tiemstra 2007). Frowning and pursing of the lips are also impaired by Bell’s palsy (Misulis 2010).

Some individuals with Bell’s palsy describe a feeling of numbness in their face, although facial sensation is left intact (Misulis 2010). Bell’s palsy can impair the formation of tears (lacrimation) as well, resulting in dryness of the eye. However, because Bell’s palsy also impairs control of the eyelids, tears may spill out of the affected eye giving the appearance of over-tearing (Tiemstra 2007; Misulis 2010). In some cases, parts of the facial nerve that supply the tongue and ear can be affected, resulting in loss of taste on the frontal two-thirds of the tongue or intensification of loud noises, also known as hyperacusis (Misulis 2010).

In most cases, the symptoms of Bell’s palsy will resolve completely. However, Bell’s palsy can cause some long-term complications. In some people, the facial nerve will not recover completely, resulting in lasting facial muscle weakness or partial paralysis (Mayo Clinic 2012a). Generally speaking, the more severe the muscle weakness/paralysis, the greater the likelihood for long-term muscle weakness. People who do not have some recovery within 21 days have a greater risk of having lasting facial muscle weakness (Ronthal 2013b).

If the facial nerve does not recover properly, some new nerve fibers may develop disorganized or misdirected connections. This can cause some facial muscles to involuntarily contract along with other muscles, a phenomenon known as synkinesis (Mayo Clinic 2012b). In addition, eye dryness and an inability to close the eyes completely can cause the cornea to become scratched, resulting in lasting problems with vision (Mayo Clinic 2012b). 

Differentiating Bell’s Palsy From Stroke

Both Bell’s palsy and a stroke can cause paralysis of one side of the face. However, Bell’s palsy and stroke can usually be differentiated by the presence of other symptoms (Fahimi 2013).

By definition, Bell’s palsy only affects the facial nerve, so the symptoms will be limited to facial muscle paralysis/weakness, decreased tear formation, and problems with taste. Although a stroke can cause similar symptoms, a stroke may also cause other symptoms, such as problems speaking or slurred speech, trouble understanding others, paralysis of the arm or leg on the same side of the body as the facial paralysis, vision problems, and headache (Mayo Clinic 2014).

A physical exam can help distinguish Bell’s palsy (a problem with the peripheral nerves) from a stroke (a problem with the central nervous system), which, unlike Bell’s palsy, will typically cause problems with the muscles of the lower face only (Holland 2004; Misulis 2010; Kölln 2011). As a result, a stroke will typically not cause weakness of the eyelid and forehead, whereas Bell’s palsy can cause impairment of these regions of the face. Generally, when paralysis is caused by a stroke, additional muscles on the same side of the body are usually involved (A.D.A.M. 2013).

Fortunately, emergency room physicians are generally very good at differentiating stroke from Bell’s palsy. Medical attention should be sought when symptoms of facial paralysis begin to appear irrespective of whether they are thought to be caused by Bell's palsy or stroke (Fahimi 2013).

6 Diagnosis

Bell’s palsy is a clinical diagnosis based on symptoms as well as history and physical exam findings (Misulis 2010). The physician may ask the patient to “show me your teeth” (for palsy of lower facial muscles) and “close your eyes” (for assessing upper facial muscles). The timing of onset of symptoms is also important, as Bell’s palsy typically has a sudden onset and progression as opposed to other causes of facial palsy such as tumors, which typically cause a gradual progression of muscle weakness over the course of weeks (Baugh 2013).

Pregnancy, diabetes, and recent influenza or other upper respiratory illnesses are also suggestive (Baugh 2013). Multiple family members with a history of Bell’s palsy may also point to the diagnosis. Notably, certain familial cases of Bell’s palsy may be associated with increased risk of lasting problems with control of the eyelid, dry eye, and “crocodile tears” (Zaidi 2005).

Examination of the ear, mouth, head, neck and skin is also important. Polyps in the ear may be a sign of cholesteatoma, a growth of skin tissue that can compress the facial nerve. Careful examination of the soft palate, tongue, and tonsils can help rule out Ramsay Hunt syndrome (a syndrome linked to varicella zoster virus infection that causes facial paralysis and a characteristic rash) or a parotid tumor (tumor of a salivary gland found in the cheek). Finally, the skin should be carefully examined for signs of Lyme disease (ie, circular, outwardly expanding rash), which can also cause facial palsy (Holland 2004; Mosshammer 2013). Notably, although Bell’s palsy is rare in children younger than 10 years old, up to 50% of reported cases of facial paralysis in this population are attributable to Lyme disease (Zandian 2014).

Additional testing is not typically needed for Bell’s palsy. However, laboratory tests such as a complete blood count (CBC), erythrocyte sedimentation rate (ESR) (Kassner 2012), C-reactive protein (CRP), Lyme titer, electrolytes, blood urea nitrogen (BUN), creatinine, and liver function tests may help if another cause of facial weakness is likely. Imaging studies such as magnetic resonance imaging (MRI) may also help rule out a tumor in the case of a gradual onset of facial weakness/paralysis (Misulis 2010).

Electroneurography can help provide prognostic information for people with complete facial muscle paralysis. Electroneurography uses electricity to stimulate the facial muscle on both sides of the face. The response of the facial muscle evoked by the stimulus is lessened on the side of the face affected by Bell’s palsy, and the degree of nerve degeneration can be quantified by comparing the responses on both sides of the face. People with Bell’s palsy whose muscle response is found to be weakened by ≥90% in the first three weeks are more likely to have long-term facial muscle weakness or trouble with involuntary movements of facial muscles than those with less severe findings (Gilden 2004).

The severity of Bell’s palsy can be graded using different scales. Two commonly used systems are the House-Brackmann Facial Nerve Grading System and the Sunnybrook Facial Grading System (Ng 2013). The House-Brackmann system allows clinicians to classify facial nerve problems into six different categories based on facial muscle strength and function and the appearance of the face at rest. The system also allows clinicians to evaluate the recovery and monitor disease progression and the response to treatment (Reitzen 2009; Yen 2003). The Sunnybrook scale measures facial symmetry at rest and during voluntary movements as well as involuntary muscle movements and scores them on a scale of 0 to 100. Although both systems can be used to help clinicians assess the severity of Bell’s palsy, they may not adequately assess aspects of Bell’s palsy such as facial comfort and problems with tearing that can affect quality of life (Ng 2013).

7 Conventional Treatment

Conventional treatment for Bell’s palsy hinges on corticosteroids. Corticosteroids are used to reduce inflammation and help increase the likelihood of recovery of facial muscle function (Lampert 2012; Baugh 2013; Gilden 2004; Ronthal 2013b). A 10-day course of corticosteroids, such as 10 days of 50 mg of prednisolone or 60 mg prednisone for 5 days with a 5-day tapered dose, initiated within 72 hours of the onset of symptoms, is often used (Baugh 2013). Antiviral medications, such as acyclovir (Zovirax®) and valacyclovir (Valtrex®) can be added to the corticosteroid regimen, but studies have been inconclusive as to whether antivirals offer any significant benefit (Baugh 2013; Ronthal 2013b; Lampert 2012).

The impaired tearing that accompanies Bell’s palsy can put the eye at risk for damage. The cornea can become dry and scratched, which can lead to permanent vision problems. It is recommended that, while awake, patients should use artificial tears every hour, and at night they should apply ophthalmic ointments. Eye patches or protective glasses may also help (Ronthal 2013b).

Surgery

Surgical decompression of the facial nerve may be indicated in some cases of Bell’s palsy. The facial nerve paralysis and subsequent damage caused by Bell’s palsy is thought to be due to swelling of the facial nerve. Surgical decompression of the facial nerve at its narrowest point may help improve outcomes for people with persistent, severely diminished (greater than 90% at two weeks) function (Gilden 2004; Koshal 2013; Tiemstra 2007). However, surgery for Bell’s palsy remains controversial. It is not clear how effective facial nerve decompression is at improving outcomes, as there are not enough well-designed clinical trials to fully determine its benefits (McAllister 2011; Tiemstra 2007; Baugh 2013).

Other surgical treatments are being developed to help people with long-term facial paralysis after Bell’s palsy. These include repair of the damaged facial nerve and nerve transfers/grafts. This latter option involves using a different nerve, such as the undamaged facial nerve on the other side of the face, as a source of healthy nerve fibers to connect parts of the damaged nerve (Hontanilla 2014). Another treatment involves transferring a muscle from elsewhere in the face to help restore movement to that area of the face (Koshal 2013). Although surgery may be beneficial for the treatment of Bell’s palsy in some cases, these surgical techniques may cause side effects such as hearing loss (Baugh 2013).

8 Novel and Emerging Treatments

Infusion Therapy

Infusion therapy is an approach for treating Bell’s palsy using corticosteroids mixed in an infusion solution containing dextran and pentoxifylline. The corticosteroids help reduce inflammation of the facial nerve and the combination of dextran and pentoxifylline increase blood flow to the nerve, helping it recover from the deleterious effects of the inflammation (Kinishi 1989). Although this approach has not been heavily researched in recent years, multiple studies in Europe and Asia have found it to be an effective method of treating Bell’s palsy and suggested it may be more effective than steroids alone (Sittel, Stennert 2000; Sittel, Sittel 2000; Kinishi 1989; Kinishi 1991). One study compared the effectiveness of 7 days of infusion therapy with 500 mL of dextran solution plus 500 mg of hydrocortisone (starting at 500 mg and tapering down to 100 mg) to oral hydrocortisone. Patients with complete paralysis who received infusion therapy had a significantly better recovery rate compared to the oral hydrocortisone group (Kinishi 1989). Another study by the same investigators modified the infusion therapy by adding pentoxifylline. It was found that 87% of the patients with complete palsy had total recovery when treated with modified infusion therapy compared to 68% of those receiving oral steroids (Kinishi 1991). Finally, a study of 239 people with Bell’s palsy found that a dextran and pentoxifylline infusion combined with prednisone (starting dose 250 mg and tapering over 18 days) provided total recovery (based on the House-Brackmann scale) in 92% of people with complete facial paralysis and 97% of people with partial facial paralysis; results were superior when therapy started within 3 days of developing palsy (Sittel, Stennert 2000; Sittel, Sittel 2000).

Photobiomodulation/Laser Therapy

Photobiomodulation/laser therapy utilizes different wavelengths of light to help repair cells. One study examined the effects of laser treatments using laser light with wavelengths of 660 and 780 nm on Bell’s palsy in a 3-year old child. The treatments, which began shortly after the onset of the facial paralysis, lasted for 15-30 minutes at a time. After 11 sessions over the course of three weeks, the child’s facial muscle function had returned to normal (Fontana 2013). Another study found that 12 sessions with either a laser at 760 nm or a LED light of 850 nm also cured or resulted in significant improvement in 11 of 14 patients with Bell’s palsy (Colombo 2012). In 2014 the efficacy of low-intensity and high-intensity laser therapy was investigated in a double-blind, randomized, controlled trial on 48 subjects with Bell’s palsy. The participants were divided into three groups: 1) high-intensity laser therapy plus facial massage and exercise, 2) low-intensity laser therapy plus facial massage and exercise, and 3) facial massage and exercise only. The laser therapy was administered to 8 points on the affected side of the face 3 times weekly for 6 consecutive weeks. Recovery of facial function was measured at 3 and 6 weeks following treatment using the House-Brackmann scale and the facial disability scale. The researchers concluded “both [high-intensity laser therapy] and [low-intensity laser therapy] are effective physical therapy modalities for the recovery of patients with Bell's palsy, with [high-intensity laser therapy] showing a slightly greater improvement than [low-intensity laser therapy]” (Alayat 2014).

Hyperbaric Oxygen Therapy

Hyperbaric oxygen therapy involves sitting in a pressurized (hyperbaric) chamber breathing 100% oxygen for approximately an hour. These treatments increase the amount of oxygen in the blood and may help increase oxygen delivery to the facial nerve, thus helping speed recovery after Bell’s palsy (Holland 2012). Although there is a scarcity of well-designed randomized controlled trials examining the effects of hyperbaric oxygen on Bell’s palsy, one study did compare the effects of hyperbaric oxygen treatments to corticosteroids for people with Bell’s palsy (Holland 2012; Racic 1997). This study used one-hour sessions in the hyperbaric oxygen chamber, twice daily, five days per week for up to 3 weeks or until recovery along with oral placebo, compared to normal atmospheric oxygen (21%) with 450 mg of prednisone delivered over eight days. After 9 months, greater than 95% of the people receiving hyperbaric oxygen therapy had fully recovered compared to less than 76% of those receiving prednisone. Furthermore, the hyperbaric oxygen-treated group showed significant improvement in nerve excitability measures compared to the prednisone-treated group (Racic 1997). Hyperbaric oxygen therapy represents a possible integrative therapy for the treatment of Bell’s palsy, especially as it has minimal side effects (Holland 2012).

Facial Fillers and Botulinum Injections

Two potential long-term effects of Bell’s palsy are facial asymmetry and a condition called synkinesis, in which a voluntary facial movement results in the involuntary movement of a different facial muscle group (Husseman 2008; Mayo Clinic 2012b). A case study examined the effects of injections of facial fillers (eg, hyaluronic acid gel fillers) and botulinum toxin (Botox®) injections for the treatment of a 50-year-old woman with these complications from Bell’s palsy. Multiple rounds of these treatments improved the facial asymmetry and muscle spasms, reducing pain and improving her quality of life (Wiener 2011). Botulinum injections can also be administered to the non-affected side of the face to improve facial symmetry and cosmetic appearance in people with Bell’s palsy (Kim 2013).

9 Dietary and Lifestyle Interventions

Low-Arginine/High-Lysine Diet

Since Bell’s palsy is linked to reactivation of the herpes simplex virus, dietary strategies that help fight this virus may also prove effective at treating or shortening the duration of Bell’s palsy. One strategy is to deprive the virus of the amino acids it needs to make the proteins required for replication. One amino acid that appears to be particularly important for the replication of herpes simplex virus is arginine. Multiple studies have found that depriving the virus of this amino acid can halt its replication (Inglis 1968; Tankersley 1964). Reducing the activity of the herpes simplex virus as a result of a low-arginine diet could help prevent or shorten the severity or duration of the inflammation. On the other hand, the amino acid lysine can help slow the growth of the herpes virus, as it can make it harder for the virus to utilize arginine. Increasing lysine intake, either via supplementation or by eating lysine-rich foods combined with a low-arginine diet may help combat the herpes virus. Foods high in lysine and low in arginine include dairy products, fish, and some kinds of animal proteins such as chicken. Foods such as nuts and grains are high in arginine (Gaby 2006).

Acupuncture

Acupuncture, a technique that originated in Traditional Chinese Medicine, may also be used to treat Bell’s palsy. It involves inserting small needles into specific points on the skin to harmonize the body’s life force (also known as qi [or chi]), strengthen the body, and improve the function and healing of nerves (Chen 2010). This process is generally considered to be safe and can be used to treat many of the symptoms of Bell’s palsy (Kim 2012). Multiple studies have found that acupuncture can help improve symptoms and return normal facial function in people with Bell’s palsy, but analyses of these trials have found that their quality is rather limited, which makes it hard to draw firm conclusions about the efficacy of acupuncture for Bell’s palsy (Kim 2012; Chen 2010; Cumberworth 2012). 

Biofeedback

Biofeedback is a process in which people are helped to learn how to voluntarily control muscles and body functions that were previously thought to be involuntary. It can be used to treat certain disorders, including the involuntary muscle movements that can occur after incomplete recovery from Bell’s palsy. In one small study, researchers instructed individuals with Bell’s palsy to work on keeping their eyes open during 3 mouth movements (pursing the lips, baring the teeth, and puffing out the cheeks), which can be difficult for people with Bell’s palsy. After 10 months of 30 minutes of daily training, these people had better facial symmetry than the control group that received no treatment (Nakamura 2003).

Physical Therapy

Physical therapy can also help people with Bell’s palsy recover muscle function. It appears that facial exercises, such as practicing emotional expressions (Beurskens 2006), may help improve muscle function and reduce involuntary facial movements in people with Bell’s palsy (Teixeira 2011). Physical rehabilitation, consisting of stretching and manual and verbal input, applied at an early stage resulted in overall improvement of the condition of Bell’s palsy patients and accelerated their recovery compared with non-rehabilitated patients (Barbara 2010).

10 Integrative Interventions

Methylcobalamin

Methylcobalamin is a form of vitamin B12 necessary for nervous system maintenance (Tanaka 2013). In a study on 60 subjects with Bell’s palsy of greater than 2-weeks duration, researchers divided subjects into 3 treatment groups of 20 subjects each: 500 mcg intramuscular injections of methylcobalamin 3 times weekly for 8 weeks; 60 mg daily of prednisolone tapered over 3 weeks; and methylcobalamin plus prednisolone. After one week of treatment, the methylcobalamin only and the methylcobalamin plus prednisolone groups had improved significantly, but participants receiving only the steroid showed just slight improvement. It took, on average, about 2 weeks for participants in the methylcobalamin and the methylcobalamin plus prednisolone groups to achieve complete recovery, whereas an average of 9 weeks passed before those in the steroid-only group were fully recovered. The scientists who conducted the study noted “In this study, the efficacy of methylcobalamin in patients with Bell’s palsy was confirmed. Methylcobalamin-treated patients recovered much faster than those treated with steroid alone. Recovery was seen as early as the first week of treatment” (Jalaludin 1995). Because methylcobalamin is generally considered safe and is relatively inexpensive, it represents an intriguing natural option for treating Bell’s palsy (Sickels 2008).

Acetyl-L-Carnitine

Acetyl-L-carnitine is a compound found throughout both the central and peripheral nervous systems and plays a role in a number of processes, including the processing of fatty acids. Therapeutically, it can help damaged neurons regenerate and reduce neuronal damage after injury (Flatters 2006). Studies have found that acetyl-L-carnitine is effective for treating various forms of neuropathy, including diabetic and drug-induced neuropathies (Flatters 2006; Sima 2005). A randomized, placebo-controlled study on 43 subjects with idiopathic facial palsy found that one month of daily administration of 3 g of oral acetyl-L-carnitine along with daily administration of 50 mg of methylprednisolone for 14 days sped functional recovery of the facial nerve compared to methylprednisolone plus placebo. After 10 days of treatment a measure of paralysis was reduced by half in the supplement group, whereas in the placebo group it remained the same during this period (Mezzina 1992).

Additional Support

Given the relatively benign nature of Bell’s palsy, and its typically limited disease course and good recovery prognosis in most cases, few human clinical trials have examined integrative treatment options. Nevertheless, owing to the inflammation and nerve involvement intrinsic to the pathogenesis of Bell’s palsy, several natural agents that promote neuronal health and quell inflammation may confer benefits. The following integrative therapies may be able to target some of the pathologic mechanisms underlying Bell’s palsy.

Omega-3 fatty acids. Omega-3 fatty acids are metabolized in the body into compounds that reduce inflammation (Calder 2006; Calder 2008; Simopoulos 2002). One omega-3 fatty acid, called docosahexaenoic acid (DHA), is able to inhibit signaling of a pro-inflammatory molecule called NF-ĸB and also reduces levels of other chemicals that trigger inflammation, such as tumor necrosis factor-alpha (TNF-α) and interleukin-6 (Lu 2010; Singer 2008). Eicosapentaenoic acid (EPA), another omega-3 fatty acid, has similar effects (Lu 2010). These fatty acids can also lead to the creation of different chemicals that can protect nerves from damage (Bazan 2007). As a result, a diet high in omega-3 fatty acids and low in omega-6 fatty acids may be able to help reduce inflammation (Calder 2006; Calder 2008; Simopoulos 2002), although this has not been specifically tested for Bell’s palsy. Fish oil is a good source of omega-3 fatty acids (Simopoulos 2002).

Curcumin. Curcumin is a yellow compound found in turmeric that has potent anti-inflammatory properties. It has been shown to help protect against nerve damage caused by diabetes and alcohol (Kandhare 2012; Kulkarni 2010), possibly by protecting neurons from damage caused by inflammation (Kulkarni 2010). Specifically, curcumin is able to reduce inflammation by increasing the activity of proteins that inhibit the activity of NF-ĸB, a major trigger for inflammation. Consequently, it is able to suppress the levels of many molecules that play a role in inflammation, including TNF-α, prostaglandins, and COX-2. By reducing inflammation, curcumin has been shown to protect neurons in the brain from damage from inadequate blood flow in a rat model of stroke (Liu 2013). Curcumin is also able to protect neuronal cells in culture from inflammation and toxicity produced by beta-amyloid protein, which is implicated in Alzheimer’s disease. Beneficial effects of curcumin were also observed in animal models of Alzheimer’s disease (Potter 2013). In addition, curcumin may activate genes that protect neurons from oxidative damage (Scapagnini 2006) and has been found to protect cultured neurons from oxidative damage (Huang 2011). Although the benefits of curcumin have not been tested specifically for Bell’s palsy, its benefits in other neurological conditions suggest that it could be helpful in treating the disease.

The Chronic Inflammation protocol provides a review of several additional interventions that may help reduce inflammation.

Niacin. Niacin (vitamin B3) is a vitamin that can cause blood vessels to dilate, which is why it causes flushing in many people. This increased blood flow may help speed the healing of the facial nerve. Some evidence suggests that niacin, administered orally or via intramuscular injection, may be useful in treating Bell’s palsy, although data are limited. In a series of 74 cases treated with 100-250 mg of niacin, all but one case resulted in good facial nerve response within 2 to 4 weeks (eg, an observer would be unable to point out which side of the face was paralyzed). In 39 of the 74 cases, treatment began within 2 days of the onset of paralysis and these individuals had complete recovery within 14 days (Kime 1958).

Integrative Interventions with Antiviral Properties

Given the suspected role of herpes virus reactivation in some cases of Bell’s palsy (Kennedy 2010), natural agents shown to combat viral infection may be of some benefit for those affected by Bell’s palsy, although clinical trials have yet to evaluate this hypothesis.

Licorice

Licorice is a member of the Glycyrrhiza species, which has been used traditionally to combat viral infections. It contains a compound called glycyrrhizin that has been shown in several studies to exert antiviral activity against a number of viruses, including herpes virus (Fiore 2008; Pompei 1979). In fact, the broad antiviral activity of licorice has given rise to interest in its clinical application as a broad-spectrum antiviral (Pu 2013). Animal studies show that licorice compounds mitigate the impact of HSV-1 infection and reduce HSV-1 viral replication (Sekizawa 2001).

Zinc

Zinc may be able to combat Bell’s palsy on a number of fronts. Zinc inhibits the replication of the herpes virus and has been used in multiple trials to reduce the duration of herpes outbreaks (Gaby 2006). Zinc is also important for nerve function, as zinc deficiency can impair the ability of nerves to transmit signals (O’Dell 1990; NINDS 2012).

Lysine

Lysine is an amino acid sometimes used to treat recurrent herpes simplex infections (Flodin 1997). It has not been formally evaluated in the context of Bell’s palsy, but studies have found it to be useful in combatting herpes virus-related illnesses. A double-blind, placebo-controlled study that included participants with oral-facial or genital herpes found that consumption of one gram of L-lysine three times daily for 6 months reduced the frequency, duration, and severity of herpes outbreaks (Griffith 1987). Other studies have also found that lysine supplementation can reduce the frequency of cold sores that occur during HSV-1 infection (Ozden 2011). Overall, lysine appears to be able to reduce the intensity and frequency of HSV flare-ups when used regularly (EBSCO CAM Review Board 2011).

Reishi Mushroom

The reishi mushroom, also known as Ganoderma lucidum, is a fungus that has been used medicinally for centuries in China, Japan, and Korea. Some of the components of reishi appear to have antiviral properties (Paterson 2006). Researchers have identified two different compounds in the reishi mushroom, known as GLPG (Ganoderma lucidum proteoglycan) and APBP (acidic protein bound polysaccharide), which showed strong antiviral activities against both HSV-1 and HSV-2 in vitro (Liu 2004; Li 2005; Kim 2000).

Preparations of the reishi mushroom have also shown promising results in human trials. Reishi was very effective in reducing pain caused by herpes and shingles infections that did not respond to standard treatment. Also, an herbal mixture containing reishi reduced shingles pain. In addition, another reishi-containing herbal mixture shortened the duration of symptoms in patients with oral and genital herpes infections (Hijikata 1998; Hijikata 2005; Hijikata 2007).

Much of reishi’s benefit may be due to its ability to combat immunosenescence – the normal decline of the immune system that accompanies aging. Reishi mushrooms attack and reverse immunosenescence through the combined effects of three compounds: first, a group of long-chain carbohydrates called polysaccharides; second, a unique protein named LZ-8; and third, a small group of steroid-like molecules called triterpenes (Bao 2001; Xu 2011; Yeh 2010).

Together, these three reishi components achieve the dual goals of promoting healthy immune responses against viral, bacterial, or fungal infections, while suppressing excessive or chronic inflammation that threatens long-term health.

Among its broad-spectrum immune-boosting effects are the following:

  • Reishi promotes specialization of dendritic cells and macrophages. These cells are essential in allowing individuals to react to new threats, vaccines, and cancer cells (Cao 2002; Lai 2010; Jan 2011; Ji 2011; Chan 2005).
  • Reishi's effects on dendritic cells have been proven to boost the response to tetanus vaccine. The mushroom's proteins are also under investigation as "adjuvants" to emerging cancer DNA vaccines and other immune-based cancer treatments (Lai 2010; Chu 2011; Lin 2011; Zhu 2012).
  • Reishi polysaccharide triggers growth and development of bone marrow, where most immune cells are born. Following bone marrow eradication by chemotherapy, reishi increased production of both red and white blood cells (Zhu 2007).
  • Reishi increases numbers and functions of many cell lines in the immune system, such as natural killer cells, antibody-producing B cells, and the T cells responsible for rapid response to a new or "remembered" antigen (Jan 2011; Wang 2012; Jeurink 2008).

On the other side of the immunosenescence coin, reishi's various components work to suppress inflammatory cytokines produced during chronic inflammation, as seen for example in rheumatoid arthritis, while maintaining normal acute inflammatory responses (Ji 2011; Kohda 1985; Ho 2007; Ko 2008; Xi Bao 2006). Under conditions of chronic inflammation, reishi reduces inflammatory promoters (Dudhgaonkar 2009).

Lemon Balm

Lemon balm (Melissa officinalis) is a form of mint used traditionally to treat numerous ailments, including herpes outbreaks (Yarnell 2009). Several laboratory experiments have shown lemon balm extracts possess a variety of antiviral activities against both HSV-1 and HSV-2 (Mazzanti 2008; Astani 2012; Schnitzler 2008; Geuenich 2008; Nolkemper 2006; Allahverdiyev 2004; Dimitrova 1993). Clinical trials have evaluated the efficacy of topical lemon balm preparations and shown positive results. In one trial, a lemon balm ointment improved symptoms of oral herpes compared to placebo when applied 4 times daily for 5 days; the lemon balm treatment also prevented the spread of the outbreak, and the authors suggested that lemon balm may increase the time between outbreaks (Koytchev 1999). Two additional trials involving 115 and 116 patients also found that local therapy with lemon balm extract effectively eases oral herpes symptoms (Wolbling 1994).

Propolis

Propolis is a resin-like substance obtained from beehives and has a long history of medicinal use (Natural Medicines Comprehensive Database 2012). It contains a mixture of several compounds, including flavonoids and polyphenols, many of which have anti-HSV-1 activity (Schnitzler 2010). The variety of effects that it has on the immune system, together with its anti-inflammatory properties, may allow it to help the body more effectively fight infections (Storcin 2007).

In one study, a constituent of propolis was found to significantly inhibit the synthesis of HSV in cell cultures (Amoros 1994). Another study showed that a propolis extract has potent antiviral activity against HSV-2 in cell cultures (Nolkemper 2010). Notably, an ointment containing flavonoids from propolis was more effective in aiding the healing of genital herpes lesions and reducing local symptoms than the antiviral medication acyclovir (Vynograd 2000). Propolis, as a 3% ointment, was also shown to reduce the duration of cold sores caused by oral herpes and decreased pain associated with the lesions (Ehrlic 2011).

A number of other integrative interventions shown to possess antiviral properties are presented in the Herpes and Shingles protocol.

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