[Cough-variant asthma successfully treated with a peptide leukotriene receptor antagonist]

A 47-year-old woman complained of coughing for over 5 weeks. The coughing was not relieved by bronchodilators (theophylline, beta 2-adrenoceptor agonist; procaterol), anti-allergic agents (azelastine, ozagrel), an inhaled corticosteroid (beclomethasone dipropionate), a macrolide antibiotic (clarithromycin), or codeine phosphate. A peptide leukoriene receptor antagonist (pranlukast) completely abolished the coughing and increased the cough threshold to capsaicin. The patient was given a diagnosis of cough-variant asthma because her sputum contained many eosinophils and her airway responsiveness to methacholine was slightly higher than normal. Peptide leukotriene may have contributed to the coughing. The fact that coughing associated with cough-variant asthma was abolished by a peptide leukotriene receptor antagonist is clinically important.