What Causes Burning Mouth Syndrome?

The rare medical condition leads to persistent uncomfortable sensations in the mouth and on the tongue — here's when you need to see a doctor.

Doctor examining patient's mouth


If you've ever taken a sip of scalding hot coffee or grabbed a fresh-from-the-fryer onion ring too soon, you know what it's like to burn your mouth. You likely felt that scalding sensation for minutes, maybe even hours or days afterward. Now, imagine your mouth feeling like that for years.

That's Burning Mouth Syndrome (BMS).

Here's what you need to know about this rare medical condition that's estimated to affect approximately 0.1 to 4 percent of the population.

What is Burning Mouth Syndrome?

This is a benign syndrome that causes a persistent burning sensation in the mouth and on the tongue. The most remarkable feature of the condition is that tests don't show the cause of the pain. Women in their post-menopausal years have a higher risk, and women, in general, are seven times more likely to develop BMS than men.

The symptoms of BMS can include, but aren't limited to:
•    A constant burning sensation on the tip/sides of the tongue, top of the tongue, roof of the mouth and inside of the lips
•    Sour, bitter, or metallic taste in the mouth
•    A "crawling" sensation inside the mouth

Those who suffer from BMS also report that their symptoms get progressively worse throughout the day and are least pronounced when they wake up in the morning.

What causes BMS?

The exact cause of Burning Mouth Syndrome isn't known. It's important to note, however, that BMS has been divided by the medical community into primary and secondary Burning Mouth Syndrome. Both primary and secondary BMS are thought to be neurological conditions. It's believed that primary BMS is caused by damage to the nerves in the mouth that control sensations like taste and pain.

Secondary BMS is thought to be caused by other medical conditions, such as:
•    Medications that treat high blood pressure
•    Ill-fitting dentures
•    Conditions of the endocrine system, like hypothyroidism or diabetes
•    Psychological conditions, such as stress, depression and anxiety
•    Mouth irritation from overly aggressive tooth brushing, abrasive toothpaste or drinking highly acidic drinks (like fruit juices)

Additional factors that also may contribute to developing secondary BMS are menopause; TMJ issues; stressful life events (like death or job loss); fibromyalgia; or chronic fatigue syndrome.

When do you need to see a doctor?

If you experience an unexplained, ongoing burning sensation in your mouth that gets more severe as the day goes on, it might be time to see a doctor.

In preparation for your visit, try to make notes on:
•    When you first started feeling the burning sensation
•    If the sensation is worse after any kind of activity or foods
•    Any additional medical or stress-related challenges you might also be under treatment for both before and after your burning mouth symptoms began.

Your doctor will perform various diagnostics that might include blood tests; salivary measurements; allergy tests; oral biopsies; gastric reflux tests; and psychological inventories to help narrow down the potential causes for your unexplained burning mouth pain.

How is BMS treated?

If a physician determines you have secondary BMS (BMS triggered by a related medical condition), they'll typically begin by treating that medical condition. Patients often see their BMS symptoms subside when the underlying medical condition is treated.

For those with primary BMS (BMS with no discernible underlying medical condition), treatment can be more complicated. Some therapies might include:
•    Nerve-blocking medications
•    B vitamins
•    Select antidepressants
•    Specialty oral rinses and mouthwashes 
•    Capsaicin 
•    Cognitive Behavioral Therapy (CBT) to help manage and cope with pain

The most important thing to know about Burning Mouth Syndrome is that there is help available. Consulting medical professionals can help you figure out if there's an underlying medical condition causing your pain. From there, the next steps are treating what ails you and finding ways to help you manage the pain.

Your doctor may also suggest some lifestyle changes to help you get back to that hot cup of coffee and those delicious onion rings without that burning sensation in your mouth.

That is, unless you take that too hot, too soon bite.

E. Napoletano is an award-winning journalist and the recipient of the 2019 Illinois Women’s Press Association first-place prize for her feature on the traumatic effects of family separation policies at the border.