Patients with diabetes may require larger doses of morphine than nondiabetic patients for the most effective relief of postoperative pain.

Past studies have suggested that hyperglycemia and diabetes affect patients’ responses to opiates used for pain relief. A recent Turkish study examined the postoperative use of morphine in diabetic patients.

Sixty patients undergoing elective total abdominal hysterectomy were divided into groups based on whether they did or did not have diabetes. Only analgesics with morphine were used in this study. After a loading dose given during the perioperative period, postoperative intravenous morphine was administered by the patient, as needed. Researchers monitored the amounts of morphine needed along with the patients’ pain scores and side effects.

Morphine consumption was higher in diabetic patients, especially in the first hour following surgery and in the last 24 hours. Postoperative pain was also higher in diabetic patients. More patients with diabetes required rescue doses of morphine, and more of them experienced nausea.

—Acta Anaesthesiologica Scandinavica, May 2004