Missouri Snakeroot (commonly referring to Polygala senega, also known as Seneca Snakeroot) has a history of use in North American indigenous and traditional herbal medicine. It was historically employed by Native American tribes and later by herbal practitioners for a range of conditions, particularly respiratory issues such as coughs and bronchitis. There are also scattered reports of its use as a "blood purifier" or for “glandular swellings,” which would have included swollen lymph nodes or glands. However, these uses are based on historical and traditional practices rather than modern scientific evaluation.

There is no direct scientific evidence supporting the effectiveness of Missouri Snakeroot for swollen lymph nodes or glandular issues. The traditional uses are not supported by modern clinical trials or pharmacological studies specific to this indication. Most of the documented actions of Polygala senega relate to its expectorant and mild anti-inflammatory properties, and not to direct effects on lymphatic tissue or glandular swelling. As such, its use for lymph node or gland support remains rooted in traditional herbalism, with a very low level of evidence supporting efficacy for this specific purpose.