Houttuynia cordata, commonly known as Houttuynia, has a long history of use in traditional medicine systems, particularly in East Asia (China, Japan, Korea). In Traditional Chinese Medicine (TCM), Houttuynia is regarded as a "heat-clearing" and "detoxifying" herb, often prescribed for conditions involving infection, swelling, or inflammation. One of its traditional uses includes the treatment of swollen lymph glands, especially in the context of sore throat, tonsillitis, or mumps, where lymphadenopathy (enlarged lymph nodes) is a common symptom. Preparations of Houttuynia are commonly administered as decoctions or topical applications for these issues.

However, direct scientific evidence supporting Houttuynia's efficacy in treating swollen lymph glands specifically is limited. Most contemporary research focuses on its antimicrobial, antiviral, and anti-inflammatory properties in vitro and in animal models. For example, some studies have shown it suppresses certain pathogens and modulates the immune response, potentially reducing inflammatory swelling. Yet, there are no high-quality clinical trials specifically examining its effects on lymphadenopathy in humans. Therefore, while its traditional use for swollen glands is well-documented, scientific validation remains weak.