Burning mouth syndrome is a persistent burning sensation in the mouth with no visible cause. Nothing looks wrong on examination, blood work is usually unremarkable, and most treatments that get tried are borrowed from other pain conditions. It is exactly the sort of orphan diagnosis where a well-tolerated compound gets a hearing.
Palmitoylethanolamide has one randomized double-blind controlled trial in this condition. The trial calls itself preliminary in its own title, which is a level of honesty worth matching.
There is also a piece of mechanistic evidence here that is unusual and gets almost no attention: when researchers measured PEA in the blood of people with burning mouth syndrome, it was not low. It was elevated.
Key Takeaways
- A preliminary randomized double-blind controlled trial gave ultramicronized PEA 600 mg twice daily for 60 days to patients with burning intensity above 4 on a numeric rating scale [1].
- A statistically significant reduction in burning sensation was recorded at the end of active treatment in the PEA group compared with placebo [1].
- The trial was small: 35 patients were eligible and 6 withdrew before the end of treatment [1]. No treatment-related side effects were observed or reported by patients or physicians [1].
- A systematic review of nonpharmacologic treatments places PEA among agents with short-term pain relief reported in anecdotal placebo-controlled trials, while alpha-lipoic acid carried the largest body of supporting trials [2].
- Plasma PEA levels were significantly elevated, not reduced, in newly diagnosed burning mouth syndrome patients compared with healthy controls [3], which complicates the simple deficiency story.
What Burning Mouth Syndrome Is, and Why It Is Hard to Treat
Burning mouth syndrome is a chronic orofacial pain condition characterised by a burning sensation of the oral mucosa in the absence of identifiable local or systemic cause. Its management remains difficult and reviews of therapeutic approaches continue to describe a field without a settled first-line treatment [4].
That vacuum is why the treatment list is so long and so varied. A systematic review of nonpharmacologic treatments identified 27 randomized controlled trials and 6 open clinical trials covering 14 different interventions [2]. Fourteen approaches for one condition is a signature of an area where nothing works reliably.
The PEA Trial in Detail
The study was a preliminary randomized double-blind controlled trial designed to test ultramicronized PEA in burning mouth syndrome [1]. Patients were included if their referred burning intensity was greater than 4 on the Numeric Rating Scale, alongside other established inclusion and exclusion criteria [1]. That entry threshold matters, because it means the trial deliberately recruited people with more than trivial symptoms.
Participants were randomized to placebo or to ultramicronized PEA 600 mg twice daily for 60 days [1]. Assessment points were baseline, 30 days, 60 days, and then 4 months after treatment discontinuation [1]. Change over time was analysed with a generalized linear mixed model [1].
That fourth timepoint is genuinely unusual. Most supplement trials stop measuring the day dosing stops. Following patients four months after discontinuation asks a different and more useful question: does anything persist, or does the condition simply return.
The Result
A statistically significant reduction of burning mouth sensation was registered at the end of active treatment in the ultramicronized PEA group compared with the placebo group [1]. No side effects related to the active treatment were observed or reported, by either patients or physicians [1].
The authors conclude that the significant decrease in burning sensation suggests this naturally occurring molecule should be considered a viable therapy in the management of burning mouth syndrome, and note the appeal of a compound free of adverse effects that does not interfere with other pharmacological therapies [1].
Now the size. A total of 35 patients were considered eligible, of whom 6 withdrew prior to the end of treatment [1]. That leaves fewer than thirty completers split across two arms. A significant result in a trial that small is a reason to run a bigger one, not a reason to consider the question settled. The paper says as much by calling itself preliminary in its own title.
How It Compares With the Alternatives
The systematic review of nonpharmacologic treatments is the right place to put this trial in proportion [2]. Eleven trials tested alpha-lipoic acid at 600 to 800 mg daily for 30 to 120 days, and seven placebo-controlled studies showed significant pain relief [2]. Four trials tested topical and systemic capsaicin for 7 to 30 days, with two placebo-controlled studies revealing significant efficacy [2]. Four of five acupuncture trials offered favorable evidence of pain relief [2]. Two trials reported significant relief with tongue protectors over two to three months [2].
Ultramicronized PEA appears in the review’s list of agents where short-term pain relief was reported in anecdotal placebo-controlled trials, grouped with tocopherol, catuama, group psychotherapy, cognitive therapy and repetitive transcranial magnetic stimulation [2].
That is a fair placement. Alpha-lipoic acid has eleven trials behind it. PEA has one. Both are plausible, both are well tolerated, and only one has been tested repeatedly. Readers comparing them should weigh that difference. This site covers PEA against alpha-lipoic acid in a separate article on neuropathy, where the same asymmetry shows up.
The review’s overall verdict deserves quoting as well: evidence was collected from highly biased, short-term, heterogenous studies mainly focused on pain, with scarce data on quality of life, psychological status, taste disturbance and dry mouth, and long-term effectiveness needs more rigorous study designs [2]. That applies to the PEA trial too.
The Mechanistic Surprise
The usual story told about PEA supplementation is a deficiency story: the body makes this compound on demand in response to injury, so topping it up should help when the system is overwhelmed. Burning mouth syndrome has the data to test that assumption, and the data do not fit neatly.
Researchers measured endocannabinoid ligands and non-cannabinoid N-acylethanolamine molecules in plasma from newly diagnosed burning mouth syndrome patients and healthy subjects using liquid chromatography tandem mass spectrometry [3]. Plasma levels of PEA, but not of oleoylethanolamide, anandamide or 2-arachidonoylglycerol, were significantly elevated in patients with burning mouth syndrome compared with healthy individuals [3]. Plasma PEA, OEA and AEA levels correlated with depressive symptomatology [3]. The authors describe this as the first evidence that circulating levels of these molecules are altered in the condition [3].
Elevated rather than depleted. That could mean the body is already mounting a compensatory response that is not sufficient, which would still leave room for supplementation to help. It could also mean the simple deficiency framing is wrong for this condition. What it cannot support is the claim that people with burning mouth syndrome are running low on PEA and need to replace it.
The study size sets the ceiling on how much weight this carries: 9 patients versus 8 healthy controls [3]. It is a first observation, not an established fact about the disease.
What to Do With This
Burning mouth syndrome should be assessed properly before anything is tried, because the diagnosis is one of exclusion and several treatable causes produce similar symptoms. Reviews of therapeutic approach exist precisely because management is nuanced and often multimodal [4].
Within that, the PEA evidence is real, positive, small and preliminary. The dose studied was 600 mg twice daily of the ultramicronized form for 60 days [1], which is a concrete and testable regimen rather than a vague recommendation. Its best argument is the safety profile: no treatment-related side effects reported, and no interference with other pharmacological therapies [1]. Its weakest point is that a single small trial has not been replicated.
Frequently Asked Questions
What PEA dose was used for burning mouth syndrome?
Ultramicronized PEA 600 mg twice daily for 60 days, in patients whose baseline burning intensity exceeded 4 on a numeric rating scale [1].
Did the effect last after stopping?
The trial assessed patients 4 months after treatment discontinuation as well as during treatment [1]. The significant between-group difference is reported at the end of active treatment, so the durable-benefit question is best answered from the full paper rather than assumed.
Is PEA better than alpha-lipoic acid for this?
No comparison trial exists. Alpha-lipoic acid has eleven trials in the systematic review with seven placebo-controlled studies showing significant relief, while PEA is listed among agents with anecdotal placebo-controlled support [2].
Are PEA levels low in burning mouth syndrome?
No. Plasma PEA was significantly elevated in patients compared with healthy controls in a small study of 9 patients and 8 controls [3]. That argues against a simple deficiency explanation.
Were there side effects?
None related to active treatment were observed or reported by patients or physicians in the trial [1]. Six of 35 eligible patients withdrew before the end of treatment, and the abstract does not attribute those withdrawals to the treatment [1].
References
- Ottaviani G, Rupel K, Gobbo M, et al. Efficacy of ultramicronized palmitoylethanolamide in burning mouth syndrome-affected patients: a preliminary randomized double-blind controlled trial. Clin Oral Investig (2019). PMID 30361792
- Cabras M, Gambino A, Broccoletti R, et al. Effectiveness of Nonpharmacologic Treatments of Burning Mouth Syndrome: A Systematic Review. J Oral Facial Pain Headache (2021). PMID 34609377
- Barry A, O’Halloran KD, McKenna JP, et al. Plasma N-acylethanolamine and endocannabinoid levels in burning mouth syndrome: Potential role in disease pathogenesis. J Oral Pathol Med (2018). PMID 29436743
- Tan HL, Renton T. Burning mouth syndrome: a review of therapeutic approach. J Oral Rehabil (2021). PMID 34881535
These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure, or prevent any disease. Content is for informational purposes only and is not medical advice; consult a qualified healthcare provider before starting any supplement. As an Amazon Associate we earn from qualifying purchases.
