Agastache, particularly Agastache rugosa (often called Korean mint or Huò Xiāng in Traditional Chinese Medicine), has a long history of use in traditional herbal systems, especially in East Asia. In Traditional Chinese Medicine (TCM), Agastache is regarded as an herb that can "transform dampness" and is commonly used in herbal formulas to address symptoms such as chest congestion, cough, and other respiratory complaints. Its aromatic properties are believed to help "open" the lungs and expel phlegm. Historic materia medica texts describe its use in decoctions or teas for supporting lung function and easing congestion.

However, while this traditional use is well documented, modern scientific research directly evaluating Agastache for lung congestion or respiratory conditions is quite limited. Some laboratory studies have identified antimicrobial, anti-inflammatory, and spasmolytic properties in Agastache extracts, which could theoretically contribute to relief from respiratory symptoms, but there are no robust clinical trials substantiating its efficacy for lung congestion specifically. Therefore, its use for this condition is primarily justified by traditional use rather than contemporary scientific validation.