Epidural morphine is an effective analgesic technique for lower abdominal surgery, but pruritus is its most common side effect. Nalbuphine is an agonist–antagonist opioid and effective in treating opioid-induced pruritus. Dexamethasone is a corticosteroid with anti-inflammatory and antiallergic properties. We compared the effectiveness of intramuscular dexamethasone and nalbuphine in the prevention of epidural morphine-induced pruritus after lower abdominal surgery.Methods
One hundred and fifty, American Society of Anesthesiologists physical status I or II, patients undergoing lower abdominal surgery with epidural anesthesia were assigned randomly to three groups. Group A, group B, and group C received intramuscular normal saline (2 ml; n=50), dexamethasone (8 mg/2 ml; n=50), and nalbuphine (10 mg/2 ml; n=50), respectively, after skin closure. The occurrence and severity of pruritus were assessed at 1, 4, 8, and 12 h after surgery.Results
Pruritus occurred less frequently in group C than group B (P<0.05). At 4, 8 and 12 h postoperatively, the severity of pruritus was significantly different (P<0.05) and was significantly less in group C than group B in the intergroup comparison (P<0.05).Conclusion
Nalbuphine proved to be better than dexamethasone in the prevention of epidural morphine-induced pruritus in patients who underwent lower abdominal surgery. Prophylactic intramuscular nalbuphine (10 mg) is effective in decreasing the incidence and severity of pruritus and does not affect analgesia.