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Updated: Jun 16, 2026
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A Traditional Chinese Medicine Characteristic Therapy for Bronchial Asthma: Moxibustion
Published on: May 12, 2023
Bronchoconstriction-triggered cough is impaired in typical asthmatics
Noriyuki Ohkura1, Masaki Fujimura, Akira Tokuda
1Respiratory Medicine, Kanazawa University Hospital, Ishikawa 920-8641, Japan. nori@med3.m.kanazawa-u.ac.jp
Summary
Asthmatics have a reduced cough response to bronchoconstriction, despite increased airway responsiveness. This study investigated the cough reflex in asthma patients and healthy individuals after methacholine inhalation.
Area of Science:
- Pulmonology
- Respiratory Medicine
- Clinical Investigation
Background:
- Cough is a vital protective reflex, yet its mechanism during bronchoconstriction remains unclear.
- Bronchoconstriction, a key feature in asthma, can be triggered by various stimuli.
- Understanding cough triggers is crucial for managing respiratory conditions.
Purpose of the Study:
- To investigate the relationship between bronchoconstriction and cough.
- To compare cough responses to methacholine-induced bronchoconstriction in asthmatics and healthy subjects.
Main Methods:
- Assessed bronchial responsiveness to methacholine (Mch) in 15 asthmatics and 20 healthy individuals.
- Quantified the number of coughs induced by Mch inhalation.
- Measured forced expiratory volume in 1 second (FEV(1)) to determine Mch concentration (PC(20)-FEV(1)).
Main Results:
- Normal subjects exhibited significant cough responses (22.5 coughs/32 min) after Mch inhalation.
- Asthmatics showed a markedly impaired cough response (median 2 coughs/32 min) to Mch-induced bronchoconstriction.
- This occurred despite asthmatics having increased airway responsiveness.
Conclusions:
- Typical asthmatics demonstrate an impaired cough response to bronchoconstriction.
- This impairment exists even with heightened airway responsiveness in asthmatics.
- The findings suggest a disconnect between airway hyperresponsiveness and cough reflex sensitivity in asthma.
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