A 47-year-old woman presented to a pain management clinic for follow-up treatment of chronic lower back pain and random urine drug monitoring. Prior medical and surgical history included diarrhea-predominant irritable bowel syndrome, successfully treated with diphenoxylate-atropine (Lomotil, manufactured by Pfizer), and sleeve gastrectomy for morbid obesity. Her current opioid pain regimen consisted of oxycodone (with morphine equivalent dose of 129 mg), to which the patient had been transitioned from methadone in the previous year.