ArticleERJ open research2026
Effect of l-menthol on breathlessness and exercise endurance in COPD: a randomised crossover trial.
Article in ERJ open research, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Authors and funding
5 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Background and objective: Breathlessness is a leading cause of disability and reduced quality of life in COPD. Inhaled l-menthol may reduce breathlessness but data on its effect on exertional breathlessness is limited. We aimed to evaluate the effect of inhaled l-menthol on exertional breathlessness and exercise capacity in patients with COPD. Methods: This was a double-blinded, randomised (ratio 1:1), crossover trial (RCT) of l-menthol inhalation Results: Compared with placebo, inhaled l-menthol reduced breathlessness intensity at isotime (mean difference -0.8, 95% CI -1.6-0.0; p=0.042), corresponding to a moderate effect size (Cohen's d= -0.49). Isotime breathlessness unpleasantness (-0.7, -1.7-0.3) and emotional response score was lower with L-menthol (-2.2, -4.4-0.0). Leg discomfort (-0.5, -1.3-0.2) was numerically lower, EET was longer (0.9 min, -0.7-2.5) and physiological responses were unchanged. Conclusion: Inhalation of l-menthol reduced the intensity and emotional response of exertional breathlessness and increased the EET compared with placebo in patients with COPD. The unchanged physiological responses support a central brain effect and l-menthol might be a promising new treatment.
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