Abstract
We report a case of endocrine dysfunction caused by the long-term use of opioids for chronic nonmalignant pain treatment. A 51-year-old man was diagnosed with Complex Regional Pain Syndrome (CRPS) of his lower extremity. He underwent neural blockade, rehabilitation, spinal cord stimulation, and medications, all of which provided adequate pain relief. Opioid therapy was initiated with morphine and was continued for 4 years until the patient was converted to continuous transdermal fentanyl. Shortly after the change, the patient began to experience a rapid decrease in body weight, a loss of appetite, and serious fatigue, and all continued for six months. Serum-hormone tests and hormone-loading tests were performed. The patient was diagnosed as having adrenal insufficiency and hypogonadism induced by opioid therapy. Because opioid therapy could not be stopped as a result of the ongoing pain,,hydrocortisone replacement therapy was started. Fatigue and loss of appetite disappeared immediately, and the body weight slowly recovered over a period of nine months