Topical Herbal Medicine for Chemotherapy-Induced Peripheral Neuropathy

Our laboratory previously discovered a unique and simple‐to‐apply neuroprotective methodinvolving topical menthol treatment. In an animal model, this approach demonstratedprominent anti‐inflammatory effects and improved behavioral outcomes (published in theJournal of Neuroinflammation, 2022). Based on these findings, we hypothesize that topicalmenthol can alleviate chemotherapy‐induced peripheral neuropathy (CIPN).To test thishypothesis, our team conducted a preliminary open‐label clinical study (IRB:TMANH112‐REC025) evaluating menthol‐based gloves and foot‐covers. The pilot resultsrevealed that the 8% menthol concentration significantly improved tactile sensationsensitivity via von Frey monofilament testing. Notably, after a 14‐day intervention, thetherapeutic effects appeared to persist for up to 21 days.While the small sample size inthe pilot stage limited the statistical power to detect significant differences insubjective symptoms like numbness (NRS) or overall quality of life, the trendingimprovements in physical tactile sensation warrant a rigorous validation. Therefore, thisexpanded, randomized, double‐blind, placebo‐controlled trial is scientifically designedto provide adequate statistical power to confirm the sustained clinical efficacy andsafety of 8% topical menthol treatment, while exploring underlying biological mechanismsthrough plasma‐derived small extracellular vesicle biomarker analysis in CIPN patients.