Updated: Eluxadoline is a prescription medication used to irritable bowel syndrome with diarrhea (IBS-D) in adults. Eluxadoline belongs to a group of drugs called mu-opioid receptor antaognists. The exact mechanism of eluxadoline in IBS-D is not known, but eluxadoline interacts with opioid receptors in the gut.This medication comes in tablet form and is taken 2 times a day with food.t is not known if eluxadoline crosses into human milk. Because many medications can cross into human milk and because of the possibility for serious adverse reactions in nursing infants with use of this medication, a choice should be made whether to stop nursing or stop the use of this medication.