Efficacy of aromatherapy for motion sickness: A self-controlled pre-post trial

Objective: To evaluate the clinical efficacy of aromatherapy incorporating Citrus limon essential oil on the symptoms of patients with motion sickness. Methods: A non-randomized, pre-post self-controlled design was adopted. Sixty individuals susceptible to motion sickness, recruited between October 2023 and February 2024, were enrolled in this study. The trial was conducted in two phases separated by a one-week washout period. In Phase 1, participants wore standard disposable medical masks, whereas in Phase 2, they wore disposable aromatherapy masks. During both phases, participants were exposed to a 30-minute bus ride motion stimulus under strictly controlled environmental variables (same time of day, fixed route, and designated seating). The Graybiel Motion Sickness Symptom Scale was used to assess symptom differences. Objective physiological parameters, such as blood pressure and pulse rate, were concurrently monitored, and adverse events were recorded. Results: Following the use of the aromatherapy mask, the median total Graybiel symptom score significantly decreased from 18 in Phase 1 to 6 (P < 0.001). Furthermore, the scores for typical vestibular autonomic symptoms, including nausea, pallor, cold sweating, and salivation, were all significantly reduced (P < 0.001). Throughout the intervention, physiological parameters remained stable across the entire cohort, and no intervention-related adverse events were reported. Conclusions: Aromatherapy can significantly alleviate motion sickness symptoms induced by bus rides, offering a novel non-pharmacological approach for the clinical management of motion sickness. © 2026 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.