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World J Exp Med. Mar 20, 2026; 16(1): 116584
Published online Mar 20, 2026. doi: 10.5493/wjem.v16.i1.116584
Published online Mar 20, 2026. doi: 10.5493/wjem.v16.i1.116584
Effects of olopatadine hydrochloride on substance P concentrations in nasal secretions and nasal symptoms
Fumihiko Katagiri, Saori Hatoyama-Tanaka, Risa Takayanagi, Yasuhiko Yamada, Department of Clinical Evaluation of Drug Efficacy, Tokyo University of Pharmacy and Life Sciences, Tokyo 192-0392, Japan
Tetsuo Watanabe, Masashi Suzuki, Department of Otolaryngology, Head and Neck Surgery, Oita University Faculty of Medicine, Oita 879-5593, Japan
Author contributions: Katagiri F and Watanabe T designed the research study; Katagiri F, Hatoyama-Tanaka S, Takayanagi R, Suzuki M and Watanabe T performed the research; all authors analyzed the data and wrote the manuscript; all authors have read and approve the final manuscript.
Institutional review board statement: This study was reviewed and approved by the local ethical review board (Ethics Committee of Oita University Hospital, No. B01-012).
Informed consent statement: All the individuals who participated in this study provided their written informed consent prior to study enrollment.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
CONSORT 2010 statement: The authors have read the CONSORT 2010 statement, and the manuscript was prepared and revised according to the CONSORT 2010 statement.
Data sharing statement: No additional data are available.
Corresponding author: Fumihiko Katagiri, PhD, Lecturer, Department of Clinical Evaluation of Drug Efficacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan. katagiri@toyaku.ac.jp
Received: November 17, 2025
Revised: January 20, 2026
Accepted: February 24, 2026
Published online: March 20, 2026
Processing time: 121 Days and 0.1 Hours
Revised: January 20, 2026
Accepted: February 24, 2026
Published online: March 20, 2026
Processing time: 121 Days and 0.1 Hours
Core Tip
Core Tip: Olopatadine hydrochloride (olopatadine), a histamine H1 receptor antagonist, is used to treat various allergic diseases. It has been reported that the concentration of substance P (SP) in the nasal secretions of patients with pollinosis is higher than that of healthy individuals. Furthermore, it has been reported that olopatadine inhibits release of SP. In this study, we found that olopatadine reduces the concentration of SP in the nasal secretions of patients with pollinosis, suggesting that olopatadine reduces SP concentrations and may therefore contribute to improvement in symptoms.