Qin Jiao (Gentiana macrophylla or related Gentiana species) is a well-known herb in Traditional Chinese Medicine (TCM), primarily used to dispel wind-dampness, alleviate pain, and clear heat from deficiency. Its application for ulcers—specifically gastric or peptic ulcers—is not a principal or classical indication in TCM. However, certain traditional formulations may include Qin Jiao as part of larger herbal combinations intended to reduce inflammation or discomfort associated with digestive disturbances, sometimes including ulcer-like symptoms.

The rationale in TCM for including Qin Jiao in such cases is related to its ability to clear heat and resolve dampness, which in TCM theory can contribute to the development of some gastrointestinal complaints. However, there is very limited direct historical usage or specific documentation supporting Qin Jiao as a primary treatment for ulcers, and it is not widely recognized as a central ingredient for this purpose in classical texts.

From a scientific perspective, there are only a few preliminary studies investigating the effects of Gentiana species on gastric mucosa, with some demonstrating mild anti-inflammatory or antioxidant properties in animal models, but robust evidence in humans or direct anti-ulcer effects is lacking. Therefore, the use of Qin Jiao for ulcers is primarily justified by tradition, and the evidence supporting its use for this condition is weak.