In our previous study, low-dose diluted bupivacaine 5 mg provided sufficient anesthetic level when opioid was added with local anesthetic. However, opioid-induced side effects, such as pruritus, nausea, or vomiting, could be an obstacle in common use. The aim of this study is to evaluate whether DXM-low-dose bupivacaine spinal anesthesia can provide the effective spinal anesthesia and postoperative analgesia with minimal side effect compare to the local anesthetic only group.