COSTUS – B SYRUP with powerful formulation of Bromhexine 4mg + Guaiphenesin 50mg + Menthol 2.5mg + Terbutaline 1.25 mg is works as an expectorant to facilitate the expulsion of mucus, Menthol provides a soothing effect on the throat and helps relieve irritation, while Terbutaline is a bronchodilator that relaxes the airway muscles to improve breathing