Why do so many smokers swear by this plant for lung support? Mullein leaf (Verbascum thapsus) is a traditional medicinal herb used to support lung health by loosening thick mucus and helping the body clear buildup from the airways. Mullein contains plant compounds like saponins and mucilage, which help break down sticky mucus so it can be coughed out more easily—something many smokers and ex-smokers notice quickly. When mullein is combined with elderberry, a rich source of antioxidants, and Amer