Sheep Sorrel (Rumex acetosella) has a long history of use in traditional herbal medicine, particularly in North American and European folk remedies. It is one of the key ingredients in the herbal mixture known as Essiac tea, which has been claimed to support lymphatic health and treat various ailments, including swollen lymph nodes or glands. The rationale in traditional use is largely based on the belief that Sheep Sorrel possesses "detoxifying" and anti-inflammatory properties, which could promote the drainage or health of the lymphatic system. Herbalists sometimes recommend it for general immune support and to help the body "cleanse" itself during infections that could involve lymph node swelling.

However, scientific evidence directly supporting the use of Sheep Sorrel for treating or supporting swollen lymph nodes or glands is minimal. There are a few laboratory studies suggesting that extracts of Sheep Sorrel have antioxidant and mild anti-inflammatory effects, but these have not been specifically linked to lymphatic health or the reduction of lymph node swelling in humans. No clinical trials or robust scientific studies confirm its efficacy for this condition. Therefore, its use for swollen lymph nodes is based almost entirely on traditional practice rather than scientific validation.