Question: Loperamide is an antidiarrheal agent available as an over the counter drug available to the public without a prescription. What is the mechanism by which this drug reduces diarrhea?
Answer: The noted article states that loperamide “inhibits intestinal peristalsis through mu-opioid receptor agonism, calcium channel blockade, calmodulin inhibition and decreasing paracellular permeability”. (Eggleston W et al. Loperamide abuse associated with cardiac dysrhythmia and death. 2017 Ann Emerg Med 69(1):83-86 and Baker DE. Loperamide: a pharmacological review. 2007 Rev Gastroenterol Disord. 7(suppl 3): S11-S18)