Japanese Elder (Sambucus japonica) has been used in traditional East Asian herbal medicine for a variety of ailments, including as a general anti-inflammatory and immune-supportive agent. In this context, swollen glands (enlarged lymph nodes) are often considered signs of infection or systemic inflammation, and elder plants—both European and Japanese species—have been used traditionally to help the body "clear heat" and support immune function. However, the specific use of Japanese Elder for treating swollen lymph glands is primarily rooted in traditional practices and ethnobotanical reports rather than rigorous scientific evidence.

There is limited to no clinical or preclinical research directly investigating the effects of Japanese Elder on lymphatic swelling or glandular health. Most available research on Sambucus species (mainly Sambucus nigra) focuses on antiviral and anti-inflammatory properties, which may be indirectly related to supporting the immune system during infections that could cause lymph node swelling. Still, these findings cannot be directly extrapolated to the treatment of swollen lymph glands, nor specifically to the Japanese Elder species. Therefore, while the use is justified by tradition, the strength of evidence is weak, and there is a clear lack of scientific validation for this specific indication.