Case Presentation: A 37 year-old woman with a past medical history of depression and chronic knee pain presented with complaints of two day duration non-radiating 8/10 epigastric and lower abdominal pain associated with nausea and vomiting. Vitals sings were normal. Abdomen was soft, non-distended with generalized tenderness, but without masses, rebound, or guarding. Lipase was 843. Urine drug screen was positive for opiates and morphine, but patient had received morphine in the ER. CT abdomen showed uncomplicated pancreatitis. EKG showed prolonged QTc of 534. Initially, no clear cause could be found for the pancreatitis. LFT and lipids were normal. Patient denied alcohol use, family history, or scorpion strings. Interestingly, the patient revealed that she was consuming three 72 count bottles of loperamide per day. She had been on opiates for chronic knee pain; but after starting a job that required frequent random drug screening, she started consuming large quantities of loperamide. Just prior to admission she had attempted to wean herself off loperamide, however, developed symptoms of nausea, vomiting, diarrhea, tachycardia, jitteriness, myalgias, and worsening knee pain. The patient was admitted under observation to the hospitalist service. She progressed well and had symptomatic improvement with bowel rest, IV hydration, and supportive care. Repeat Labs were unremarkable. Addiction medicine was consulted. Ultimately, the patient was discharged home with oral acetaminophen and ibuprofen with addiction medicine follow-up.
Discussion: Hospitalists frequently encounter pancreatitis, and sometimes cannot find a clear etiology. Here we present a rarer but possibly under-identified cause: loperamide abuse. With more stringent regulations to combat the opioid epidemic, many patients have turned to illicit drugs or abusing over-the-counter medications.(1) Loperamide (marketed as Imodium) has become one of these medications of abuse.(2,3) Popularized as the “Poor Man’s Methadone,” Loperamide acts on mu receptors. (2-9) In recommended doses only trace amounts cross the blood-brain barrier, with the primary effect being gastrointestinal.(2,3,5-7,9) When consumed in high enough doses, however, a sufficient amount of Imodium is absorbed to act on central opiate receptors to prevent withdrawal symptoms and produce a euphoric effect.(2,5,6,9) Loperamide is readily available OTC and not detected on drug screens, making it an attractive option for patients who may be subject to drug screening.(2,7) This also makes it difficult for hospitalists to identify as a medication of abuse. Loperamide at toxic levels has been documented to cause pancreatitis, fatal cardiac arrhythmias (Torsades de Pointes), and respiratory suppression.(5,7,10-14) This patient presented with acute pancreatitis and had findings of QTc prolongation. Unfortunately, like the patient presented here, patients attempting to discontinue use are at risk for developing opiate withdrawal symptoms.(2,6,15) Unlike prior cases reported, our patient presented with multiple adverse effects from loperamide abuse.
Conclusions: As we confront the opiate epidemic, we need to recognize new substances of abuse that can adversely affect our patients. Loperamide, with its potential for abuse and life threatening toxicity, has unfortunately emerged as one. Hospitalists should be aware of the side effects of loperamide abuse including pancreatitis and QTc prolongation.