Auricular acupuncture (AA) is known to be effective in treatment of various pain conditions, but still there have been no randomized controlled studies of AA for treatment of acute postoperative pain. Therefore we tested whether AA of specific points is superior to sham acupuncture for complementary analgesia after total hip arthroplasty in a patient-anesthesiologist-evaluator-analyst blinded study. The patients were randomly allocated to receive true AA (lung, shenmen, thalamus and hip points) or sham procedure (4 non-acupuncture points on the auricular helix). Permanent press AA needles were retained in situ 3 days after surgery. Postoperative pain was treated with intravenous piritramide (opioid receptor agonist with analgesic potency of 0.7 compared with morphine) using a patient-controlled analgesia (PCA) pump. The time to the first analgesic request, the amount of postoperative piritramide via PCA and pain intensity on a 100-mm visual analogue scale (VAS-100) were used to evaluate postoperative analgesia. Intraoperative anesthetic requirement, incidence of analgesia-related side effects, inflammation parameters and success of patients' blinding were also recorded. Fifty-four patients (29 AA and 25 controls) completed the study. Piritramide requirement during 36 h after surgery in AA group was lower than in control: 37+/-18 vs. 54+/-21 mg; mean+/-SD; P=0.004. Pain intensity on VAS-100 and incidence of analgesia-related side effects were similar in both groups. The differences between the groups as regard patients' opinions concerning success of blinding were not significant. Findings from our study demonstrate that AA could be used to reduce postoperative analgesic requirement.