Background: Common adverse side effects related to the use of neuraxial opioids in the obstetric population include nausea, vomiting, and pruritus. Serotonin (5-HT3) receptor antagonists, in particular ondansetron, have been identified as possible antipruritic agents. It was reported that dexamethasone plus ondansetron is more effective than ondansetron for prevention of postoperative nausea and vomiting but no additional effect on treating pruritus.

Objectives: The purpose of this study is to compare the effect of prophylactic ondansetron versus ondansetron plus dexamethasone after cesarean section on pruritus and postoperative nausea and vomiting (PONV).

Methods: A prospective randomized double blind study that will be conducted between June 2016 and June 2017. Patients will be randomly allocated into two groups. The first group will receive 4 mg intravenous (IV) ondansetron while the other group will receive 4 mg IV ondansetron plus 8 mg dexamethasone.

A prospective randomized double blind study will be conducted between June 2016 and June 2017. The sealed envelope technique will be used to randomly allocate females scheduled for elective cesarean section into two groups. After obtaining informed consent, all eligible patients will receive spinal anesthesia. The first group will receive 4 mg intravenous (IV) ondansetron with 2 ml saline while the other group will receive 4 mg IV ondansetron plus 8 mg (2 ml) dexamethasone.

Inclusion Criteria:

• American Society of Anesthesiology physical status 1 and 2
• Scheduled for elective c-section surgery under spinal anesthesia

Exclusion Criteria:

• Patients with cardiac and psychological problems
• Patients who take sedatives or narcotics
• Patient who have allergy to study drugs