Broncholase ayrup is specifically formulated to contain two expectorants that increase the volume of secretions in the respiratory tract to facilitate their removal by ciliary action & coughing. This is achieved by a reflex irritant effect on the gastric mucosa. Chlorpheniramine maleate in Broncholase syrup blocks competitively the effects of histamine on H1 receptors & prevents the constrictor responses to histamine of bronchial smooth muscles. It reduces various allergic symptoms.