Polygonatum species (commonly known as Solomon's Seal) have a long-standing history of use in traditional Chinese medicine (TCM) and other herbal systems, primarily for nourishing yin, moistening dryness, and relieving coughs—especially dry coughs. The root, often referred to as "Yu Zhu" (Polygonatum odoratum), is included in classical TCM texts such as the Shennong Bencao Jing and is described as having moistening and lung-supplementing properties. In TCM theory, dry coughs are often due to yin deficiency or dryness of the lungs, and herbs like Polygonatum are prescribed to restore moisture and soothe irritation.

Despite this rich traditional background, modern scientific evidence directly supporting the use of Polygonatum for dry cough is limited. Some laboratory studies suggest that extracts of Polygonatum have anti-inflammatory and immunomodulatory effects, which could theoretically provide benefit in certain respiratory conditions. However, there are no robust clinical trials or meta-analyses confirming its efficacy specifically for cough, and most evidence remains anecdotal or based on traditional usage patterns. Thus, its use for dry cough is primarily justified by historical and traditional practices rather than by strong scientific validation.