Platycodon, also known as Platycodon grandiflorus or balloon flower, has a long history of use in traditional East Asian medicine, particularly within Traditional Chinese Medicine (TCM) and Korean herbal practices. The root, referred to as "Jie Geng" in Chinese, is traditionally used to support the respiratory system, specifically targeting the throat and lungs. It is considered to have expectorant properties, meaning it helps expel phlegm and supports the health of mucus membranes in the respiratory tract. Platycodon root is often included in formulas to "open up" the lungs, soothe sore throat, and assist with coughs associated with excess phlegm or inflammation of the mucus membranes.

While there is a strong tradition supporting its use for these purposes, scientific validation is limited but growing. Some studies have identified saponins and other compounds in Platycodon root that exhibit anti-inflammatory and expectorant effects in animal and in vitro models, which may help explain its traditional usage. However, large-scale, high-quality clinical trials in humans are lacking. As such, its use to support mucus membranes is mostly justified by tradition, with some preliminary scientific support.