Why does my mouth burn?

February 25, 2019

Burning mouth disorder is miserable. Of course, so are most disorders, which is maybe why this condition is also knows as burning mouth syndrome (not much better), glossodynia (what?), stomatodynia (okay…), oral dysesthesia (this feels made up) and glossopyrosis, to name a few. The good news is that is not too common, around 1% – 6% by most estimates. The bad news, if you’re female, is that burning mouth disorder occurs primarily in women. The worse news is that it tends to occur in the 5th decade of life or older, so while sufferers have this to contend with in addition to the other issues that keep them company as they age.

Burning mouth by any other name still, well, burns. It is characterized as a persistent burning sensation in one or more areas in the mouth, with the tongue being a common site. As you would expect, these people also experience altered taste and dry mouth or xerostomia. The good news is that they often do not have a dry mouth, it just feels that way. The kicker is that to be diagnosed as having burning mouth disorder, you need to experience this sensation for at least 2 hours per day for at least 3 months. Once you have qualified as a burning mouth sufferer, it is important that your health care provider understands if you are primary or secondary. No fear, the distinction is easy: primary burning mouth disorder has no demonstrated cause and secondary burning mouth disorder does have a demonstrated cause. Common causes are Candidiasis, ill-fitting dentures, autoimmune disease such as lichen planus, geographic tongue, atrophic glossitis, nutritional deficiencies, allergies, reflux, certain medications, and endocrine disorders (e.g. diabetes).

Diagnosing this condition and the type requires some questions from you doctor or dentist, a few laboratory tests that include checking for a fungal infection, any nutritional deficiencies, possible autoimmune conditions and a salivary flow rate test. If a primary cause, let’s say a fungal infection, is detected, it is treated and your symptoms re-evaluated. Sometimes, finding a cause for the burning sensation can be time consuming and a bit of trial and error, but with patience you can either confirm or deny the presence of an offending stimulus. If it is determined that the burning mouth disorder is primary (i.e. no identified cause) or secondary (but you cannot change the reason e.g. certain medications), how can you manage the burn? Usually, combination treatments are suggested: supplements such as zinc, alpha lipoic acid are common; swishing certain medications that reduce the burning sensation; sometimes anti-depressant or anti-convulsant medications are used if these other approaches don’t work. Sometimes psychological interventions, such as cognitive-behavioural therapy, are used if a person’s anxiety and stress are increased by having a tongue that is constantly on fire.

One reason for so many approaches is that we are not really sure why some people develop this condition. Of course, hypotheses abound…but they all seem to share some common qualities: essentially, it is (probably) a dysfunction of pain nerves called “c fibres.” This (again, probably) dysfunction occurs at the site of the burning sensation, like the tongue, and (*sigh* probably) where this information is ultimately processed (in the brain). Conditions that have simultaneous peripheral and central sensitization mechanisms are notoriously difficult to manage, which is why the prognosis for conditions like burning mouth disorder are uncertain.

If you have questions about burning mouth disorder or would like to discuss this further with Dr. Shackleton, please do not hesitate to contact our office.


A Population-Based Study of the Incidence of Burning Mouth Syndrome
John J. Kohorst, Alison J. Bruce, Rochelle R. Torgerson, Louis A. Schenck, Mark D. P. Davis Mayo Clin Proc. Author manuscript; available in PMC 2015 Nov 1. Published in final edited form as: Mayo Clin Proc. 2014 Nov; 89(11): 1545–1552. Published online 2014 Aug 28. doi: 10.1016/j.mayocp.2014.05.018 PMCID:  PMC4532369

Burning Mouth Syndrome: Aetiopathogenesis and Principles of Management
L. Feller, J. Fourie, M. Bouckaert, R. A. G. Khammissa, R. Ballyram, J. Lemmer Pain Res Manag. 2017; 2017: 1926269. Published online 2017 Oct 18. doi: 10.1155/2017/1926269 PMCID:  PMC5664327