Is Capsaicin Effective in Relieving the Symptoms of Burning Mouth Syndrome? A Systematic Review.

backgroundBurning Mouth Syndrome (BMS) is a type of chronic orofacial pain characterised by a burning sensation inside the mouth without an apparent cause. Capsaicin has been used to manage the symptoms of this syndrome, but there is still no consensus on its effectiveness.

objectiveTo assess whether capsaicin, when used topically or systemically, is able to alleviate the symptoms of BMS.

methodsAn extensive search was carried out in seven databases and grey literature up to November 2025. There were no restrictions regarding the date or language of publication.

resultsThe search resulted in 782 articles, of which 4 were included. The methodological quality of the studies was assessed using the Risk of Bias in Systematic Reviews (ROBIS) tool and the certainty of evidence was performed according to Grading of Recommendations, Assessment, Development and Evaluation (GRADE). Regarding capsaicin administration, 3 studies used topical application and 1 used systemic application. Concentrations ranged from 0.000354% to 0.25%, three times a day, for 1-8 weeks. Regardless of the administration method, a reduction in patient-reported pain scores was observed. Risk of bias assessment showed that three randomised studies presented a moderate risk, while the only non-randomised clinical trial presented a critical risk. The overall certainty of the evidence was low or very low for the outcomes assessed.

conclusionEvidence suggests that capsaicin is effective in relieving BMS symptoms. However, this result should be interpreted with caution due to the low quality of the evidence obtained to support its use.