Abstract
Opioid-induced hyperalgesia (OIH) is a paradoxical response in which opioid therapy leads to increased pain sensitivity. Frequently underdiagnosed, it poses significant challenges in pain management, especially in patients with complex oncologic or postoperative pain.
A 44-year-old man with multiple myeloma and a history of spinal metastasis presented postoperatively following T12 laminectomy and spinal fusion. Despite escalating morphine doses and adjunctive medications for postoperative pain, his symptoms worsened, with increasing pain scores, burning allodynia, and poor functional improvement. His total daily morphine milligram equivalents (MME) rose from 260 to 360 without relief. Neurologic causes and surgical complications were ruled out.
Suspecting OIH, we rotated the patient from morphine to oxycodone (long- and short-acting) and IV hydromorphone using a 1:1 MME conversion, and increased adjuvant gabapentin. Within 12 hours, the patient reported marked pain improvement and resolution of allodynia. He required fewer breakthrough doses and was discharged on postoperative day 9 with an MME of 240.
This case highlights the importance of identifying OIH in patients with worsening pain despite opioid escalation. Risk factors such as renal impairment and psychological stressors may contribute to its onset, but future studies would have to evaluate this further. Opioid rotation can rapidly reverse symptoms. Clinicians should maintain a high index of suspicion for OIH as early recognition and intervention can significantly improve outcomes and reduce opioid burden.