Background: Intrathecal morphine provides effective postoperative analgesia, but their use is
associated with numerous side effects, including pruritus, nausea, vomiting, urinary retention, and
respiratory depression. Pruritus is the most common side effect with a reported incidence of 58–85%.
Objectives: This prospective, randomized, and double‑blinded study was performed for women
scheduled for cesarean delivery using spinal anesthesia to compare nalbuphine and ondansetron
in the prevention of intrathecal morphine‑induced pruritus.
Patients and Methods: Ninety women after spinal anesthesia with hyperbaric bupivacaine and
intrathecal morphine patients randomly divided into three groups. Women in placebo group (P group)
received 4 ml of normal saline intravenous (IV) injection, nalbuphine group (N group) received
4 ml of a 4 mg nalbuphine IV injection, and ondansetron 4 group (O group) received 4 ml of a
4 mg ondansetron IV injection, immediately after delivery of the baby. Studied women observed in
postanesthesia care unit for 4 h. The primary outcome measures success of the treatment, defined as
a pruritus score 1 (no pruritus) or 2 (mild pruritus ‑ no treatment required) at 20 min after treatment.
Results: Although, three was no significant difference between the three studied groups regarding;
score 1 pruritus, while, score 2 pruritus (mild pruritus ‑ no treatment requested) was significantly
high in N and O groups compared to placebo group. Pruritus score 1 (no pruritus) plus pruritus
score 2 were significantly high in N and O groups compared to placebo group (20 cases, 20 cases,
5 cases; respectively, P = 0.008). In addition; score 3 pruritus (moderate ‑ treatment requested)
was significantly less in N and O groups compared to placebo group.
Conclusion: Nalbuphine and ondansetron were found to be more effective than placebo
for prevention of intrathecal morphine‑induced pruritus in women undergoing cesarean