Clinical trial of bromhexine in severe chronic bronchitics during winter.

In a double-blind, controlled cross-over trial, the effect of the mucolytic drug bromhexine (24 mg or 48 mg daily) was compared with a placebo over a period of 14 weeks in 21 severe chronic bronchitics (mean FEV 0·8 1.). Each of the three treatment regimes was continued for four weeks with intervening single weeks on placebo tablets. As the subjects were outpatients, sodium fluorescein incorporated in the tablets was used as a drug marker. Satisfactory data were obtained in 18 patients. There was no significant improvement in clinical condition or ventilatory capacity nor change in sputum properties throughout the period of study. No side effects or significant change in blood values were detected.