Are beta(2)-agonists effective treatment for acute bronchitis or acute cough in patients without underlying pulmonary disease? A systematic review

OBJECTIVE our goal was to determine whether beta (2)-agonists improve the s ymptoms of acute bronchitis or acute cough in patients who do not have unde rlying pulmonary disease. STUDY DESIGN We performed a systematic review including meta-analysis. DATA SOURCES We included randomized controlled trials comparing beta (2)-ag onists with placebo or alternative therapies identified from the Cochrane L ibrary, MEDLINE, EMBASE, conference proceedings, Science Citation Index, th e System for Information on Grey literature in Europe, and letters to manuf acturers of beta (2)-agonists. OUTCOME MEASURED We measured duration, persistence, severity or frequency o f cough, productive cough, and night cough; duration of activity limitation s; and adverse effects. RESULTS Two trials in children with cough and no obvious airway obstruction did not find any benefits from beta (2)-agonists. Five trials in adults wi th cough and with or without airway obstruction had mixed results, but summ ary statistics did not reveal any significant benefits from beta (2)-agonis ts. Studies that enrolled more wheezing patients were more likely to show b enefits from beta (2)-agonists, and in one study only patients with evidenc e of airflow limitation were more likely to benefit, Patients given beta (2 )-agonists were more likely to report tremor, shakiness, or nervousness tha n those in the control groups. CONCLUSIONS There is no evidence to support using beta (2)-agonists in chil dren with acute cough and no evidence of airflow obstruction. There is litt le evidence that the routine use of beta (2)-agonists for adults with acute cough is helpful. These agents may reduce symptoms, including cough, in pa tients with evidence of airflow obstruction, but this potential benefit is not well-supported by the available data and must be weighed against the ad verse effects associated with beta (2)-agonists.