Immediate acupuncture with GB34 for biliary colic: protocol for a randomised controlled neuroimaging trial.

Introduction: As the main manifestation of gallstone disease, biliary colic (BC) is an episodic attack that brings patients severe pain in the right upper abdominal quadrant. Although acupuncture has been documented with significance to lead to pain relief, the immediate analgesia of acupuncture for BC still needs to be verified, and the underlying mechanism has yet to be covered. Therefore, this trial aims first to verify the immediate pain-alleviation characteristic of acupuncture for BC, then to explore its influence on the peripheral sensitised acupoint and central brain activity.