Burning Mouth Syndrome

Burning Mouth Syndrome or BMS is something I rarely see in my patients. BMS is a burning, stinging, or itching in any portion of the mouth, including the tongue, lips, or cheeks. Other names for the condition are glossopyrosis, glossodynia, oral dysesthesia, sore tongue, stomatodynia, and stomatopyrosis. There are two types of BMS; primary and secondary. Primary BMS is when there is no underlying disease causing the symptoms.

Conversely, secondary BMS is caused by another disorder, such as an infection of the mouth or poorly fitting dentures. About one million Americans suffer from it. Because primary BMS is so rare, there is little research on it. Since investigations into the cause and treatment are lacking, patients have few options for diagnosis and treatment, leading to prolonged suffering. Today I will talk about what we know and possible treatment options for Burning Mouth Syndrome. Much of the information I give today is from this paper. It is very scientific but has much more information than I cover in this post.

Who Is At Risk For BMS?

The patients most at risk for it are female, especially pre and post-menopausal age women, People with depression and anxiety, and people with chronic GI and urogenital disease. The secondary form is associated with thyroid disease, psychiatric illnesses, oral infections, drug use, dental treatment, vitamin/mineral deficiencies, and numerous other conditions. 

The condition has so many origins that finding the cause is very difficult and can involve healthcare practitioners from many specialties. However, because many sufferers have GI symptoms, gastroenterologists treat most of them. Because it is so difficult to find the origin, and the symptoms can be pretty uncomfortable, BMS can severely diminish the quality of life. (1)

What Does the Science Say?

Numerous studies link BMS to problems with the nerves of the head; especially one called the trigeminal nerve. There remains a clinical disconnect from the research as they all center on biopsies and chemical analysis not suited to medical practice, continuing to keep the cause unknown. 

Other research shows that the central nervous system can cause BMS as well. The methods used to determine the cause are not available to doctors. However, since some CNS diseases produce numerous symptoms, associations are known. For instance, patients with Parkinson's disease are reportedly five times more likely to have BMS than the general population.

There Are Three Types of Primary BMS

The research has led to the conclusion that there are three distinct subclasses in BMS. Type one is the most common. This is peripheral oral small fiber neuropathy and involves the small nerve fibers of the mouth. Type two is when the major sensory nerve of the mouth (and head) called the trigeminal nerve is the cause. This is called subclinical major trigeminal neuropathy. Related to this is trigeminal neuralgia, where the patient can experience shooting pains in the facial region. Type 3 is central deficiency in dopaminergic top-down inhibition (originating in the brain). (2) This means the pain is generated by the brain, not your mouth.

What Are the Possible Causes of BMS?

Depression, anxiety, and personality disorders occur in many BMS patients. Fifty percent of BMS sufferers have depression (3), and 86% have personality disorders. (4) The conditions may arise as a result of the BMS, or indirectly cause BMS. Therefore, depression, anxiety, and personality disorders are considered secondary or concurrent causes. (5) The reason menopause is associated with BMS is because the mucous membranes become drier, and lower hormonal levels lead to nerve degeneration. (6) 

Some foods can cause the mouth to burn. Hot peppers are obviously irritating, but a less obvious cause is cinnamon. I have had several people come to my office over the years after purchasing a pack of cinnamon gum. I would also beware of herbal toothpaste, as I have had patients complain of irritation from them as well. 

Allergies can cause BMS. The most common ones being dental metals such as zinc, cobalt, mercury, gold, and palladium. (7) Sodium lauryl sulfate from toothpaste causes dry mouth, which can lead to BMS. (8)

Because dry mouth is a cause of BMS, Sjogren's syndrome is associated with it and Lupus, which causes dry mouth as well. (9)

Numerous nutritional deficiencies can also lead to BMS. Folate and zinc deficiency, as well as B1, B2. B6 and B12 deficiencies are all associated with BMS. (10)

Some medications cause BMS; the most common are the blood pressure medications ACE inhibitors (Lisinopril) and angiotensin receptor blockers (Benicar and Diovan). Topamax, which is a migraine medication, can also cause BMS.

Some Conditions Mimic BMS

Stomatitis, atypical facial pain, atypical odontalgia, idiopathic facial arthromyalgia, pemphigoid, pemphigus, neoplastic lesions in the oral cavity, acoustic neuroma, sharp dentures or teeth, herpes simplex or herpes zoster, trauma to lingual or mandibular nerves after dental work can all mimic BMS. (11)

Diagnosis of BMS should include:

• recent mood disturbances

• dietary habits

• history of dental procedures

• use of dental prosthetics

• nutritional deficiencies

• reviewing medication 

• complete inspection of the mouth by a dentist

• measurement of salivary flow

• blood work of nutritional deficiencies

• blood glucose level

• autoimmune markers

• estrogen and progesterone levels

•  patch testing for specific allergies (12)

The primary aim of diagnosis is to EXCLUDE as many causes listed above as possible. This method allows us to rule out secondary causes and narrow down primary causes. The goal is to treat the underlying condition or change the offending medication.

What Are the Treatment Options For BMS?

The medications gabapentin (Neurontin) and clonazepam (Klonopin) have been studied and are effective in over 60% of cases. Antidepressants and antipsychotics also helped improve over 80% of patients, with 36% healing completely. Private and group therapy sessions with trained psychologists are also very effective. Additionally, hormone replacement therapy can help with perimenopausal women. (13)

Alpha-lipoic acid (ALA), an over-the-counter supplement, has been studied and effectively reduces symptoms by over 80%. The mechanism is unknown, and some trials showed no effect. 

 Amazingly, capsaicin may be the best option. Capsaicin is the hot substance found in peppers. Logic would tell us to stay away from this substance because it burns the mouth and GI tract. The reality is that it is a POTENT agent in controlling peripheral nerve pain by inhibiting substance P that our bodies produce to help signal pain. It is available OTC in pill form, but the pepper leads to abdominal pain with repeated use. (14) It is common in many topical creams not meant for oral use, but OTC Cayenne extract for oral use is available. I would caution you to use an herbalist to get the highest quality product you can. 

As always, I caution you not to self-diagnose, and this post is not intended to diagnose or treat any condition. If you suspect BMS or any other condition in your mouth, see your dentist.