[Methods of detection and treatment of bronchial hyperreactivity]

In hyperreactive patients, many non-specific stimuli such as exercise, inhalation of cold air, methacholine or carbachol are able to give rise to a temporary bronchoconstriction. Under well controlled conditions, such tests like the methacholine inhalation test, are simple, reproducible and without danger for the patient. They allow an assessment of the patients with dyspnoea or chronic cough of unknown origin, who are hyperreactive in spite of normal clinical examination results and spirometric measurements. In most cases, bronchodilator or antiasthmatic treatment allows an immediate reduction of the bronchial reactivity. This may be particularly useful in the treatment of chronic cough, where more than 90% of the patients with hyperreactive bronchi can be treated satisfactorily with the bronchodilators. The possibility of a long term reduction of bronchial hyperreactivity by drug treatment is still more controversial.