Anticholinergic bronchodilators for adult obstructive airways disease.

Quaternary anticholinergic bronchodilators offer gradual and sustained bronchodilation to patients who have asthma or chronic obstructive pulmonary disease. For asthma, the anticholinergic compounds are less potent than the beta-adrenergic agents but have useful additive bronchodilator properties when combined with beta-adrenergic agents or theophylline. They may be particularly useful in combination regimens for patients who have severe asthma and for older asthmatics. The rationale for such a combination is most compelling in the treatment of acute exacerbations of asthma. For chronic obstructive pulmonary disease, anticholinergic compounds offer greater bronchodilation than beta-adrenergic agents for most patients and are thus considered useful initial therapy in maintenance regimens.