A controlled trial of intermittent oral acetylcysteine in the long-term treatment of chronic bronchitis.

In 69 out-patients with chronic bronchitis in 6 centres the effects of acetylcysteine 600 mg daily, 3 days a week for 6 months, and a placebo have been compared in a double-blind controlled trial. Thirty-five patients were treated with the mucolytic and 34 with the dummy preparation. In the former the clinical course of the chronic bronchitis improved to a greater extent and a significantly lower number of exacerbations was observed. The advantages of long-term oral treatment with the mucolytic in chronic bronchitis suggest that it may be useful as an alternative to long-term antibiotic prophylaxis, or to complement brief courses of antibiotics, in addition to the usual physiotherapy.