In traditional Chinese medicine, runny nose and nasal congestion caused by allergic rhinitis are thought to be caused by poor circulation of fluids, often accompanied by coldness around the pit of the stomach. Xiao Qing Long Tang is a traditional Chinese medicine that warms the body and helps to expel excess fluid through sweating, thereby improving runny nose and nasal congestion. Recent research has shown that it works by acting on the body's natural defense mechanisms to suppress allergic reactions, inhibits vasodilation of the nasal mucosa which causes nasal congestion, and suppresses the release of histamine, and it is now included in the guidelines for the treatment of nasal allergies.