Background: Loperamide is used as an antidiarrheal drug and is available over-the-counter. It cannot pass the blood-brain barrier and it does not have a considerable abuse potential. It can lead to dangerous cardiac arrhythmia.Case Report: Herein, we report a 35-year-old man with a 13-year history of abusing opioids who had undergone detoxification for four times during this period. He underwent detoxification for using 200 mg loperamide daily with anticholinergic agents, clonidine, non-steroidal analgesics, and diazepam. No evidence of arrhythmia was seen in the patient.Conclusion: Tolerating high doses of loperamide could be dangerous and increases the risk of fatal cardiac arrhythmias
