Kep-LS Drops is a combination of three medicines: Ambroxol, Levosalbutamol and Guaifenesin. Ambroxol is a mucolytic which thins and loosens mucus (phlegm). Levosalbutamol is a bronchodilator which works by relaxing the muscles in the airways. Guaifenesin is an expectorant which decreases the stickiness of mucus (phlegm) and helps in its removal.