A total of 42 trials reported on this outcome. In all, four incidents were reported in the bloodletting in the auricle group, while four incidents were reported in the AD group. Side reactions included: hematoma at the bloodletting auricle (n=2 patients, 25%), red and swollen at the bloodletting auricle (n=1 patient, 12.5%), headache (n=4, 50%), palpitation (n=1 patient, 12.5%) and ankle edema (n=1 patient, 12.5%).