Breathe Clear herbal tablets are inspired by Zhi Sou San, a formula used by doctors of Chinese Herbal Medicine for centuries to relieve coughs, reduce phlegm, and soothe throat irritations. The herbs in Breathe Clear have been used across Asia for hundreds of years as a natural solution for a variety of coughs. Breathe Clear is great for: Relieving coughs Reducing phlegm Opening up the airways Supporting the lungs.