Wen Dan Tong (Warm the Gallbladder Decoction) is very popular and well-known formula in treating the symptoms of dizziness, vertigo, nausea or vomiting, insomnia, palpation, and anxiety caused by phlegm heat. The name of the formula and the indications are frequently confused because the ”wen” means warming. However, the indications and the actions of the ingredients in this formula are to clean phlegm-heat. The purpose of this article is to find out the origins of this formula and share clinical experience.