Exterior Cold was created by Zhang Yuansu, a well-known doctor in the Jin Dynasty, and was included in the book “It’s Hard to Know” by his disciple Wang Haogu in 1308 AD. The formulation contains herbs that relieve the Exterior Syndrome and are pungent in flavour and warm in nature as the main ingredient, and it is also compatible with Heat-clearing herbs. Its effect is mainly to disperse Wind, Cold and Dampness, supplemented by clearing Heat, but also beneficial to joints and pain relief. It is suitable for the treatment of exogenous Wind–Cold and Dampness, with internal Heat Pattern. The clinical application is based on dialectic points of chills, fever, no sweat, headache, and sore limbs. It is a basic formulation for the treatment of common cold, joint pains and headaches.