Background Although patient-controlled analgesia' (PCA) use has been reported in oral and maxillofacial surgery, 8 it has not been evaluated for use in orthognathic surgery. In this study, we evaluated the relationship between age, gender, and preoperative anxiety and postoperative morphine intake after orthognathic surgery in the PCA environment. Study design Fifty-one patients (34 female, 17 male) underwent orthognathic surgery. Patients' anxiety was evaluated preoperatively. All patients received morphine-based postoperative PCA. Relationship between preoperative anxiety and postoperative visual analog scale (VAS) and 24 hour morphine intake was evaluated. Patients were randomly grouped according to whether preoperative oral anxiolytics were prescribed. Results Age and VAS were correlated, as well as preoperative anxiety score and postoperative morphine intake ( P < .05). Female patients receiving anxiolytics before surgery had less morphine consumption than those who did not. Conclusion Preoperative anxiety directly influences postoperative PCA morphine intake. Anxiolytics preoperatively seem to reduce the need for postoperative analgesics.