Gui Zhi is a Wind Heat herb used to treat exterior patterns; which description best matches its use?

• A. Exterior excess only
• B. Exterior deficiency only
• C. Both exterior excess and exterior deficiency
• D. Internal deficiency

Answer: (C)

Exterior patterns can show as either excess or deficiency, and Gui Zhi’s ability to release the exterior while warming and harmonizing Ying and Wei lets it fit both scenarios. Its warm, acrid nature disperses wind-evil from the surface and opens the pores, addressing exterior conditions when the pathogen is strong (excess). At the same time, by harmonizing the protective (Wei) and nutritive (Ying) qi, it supports cases where the defensive qi is weak or deficient, helping expel the exterior without overtaxing the patient. That dual capacity is why this herb is described as suitable for exterior patterns in both excess and deficiency states. It isn’t used for interior deficiency alone, nor is it limited to exterior excess only.