why is viberzi a controlled substance
1 VIBERZI is a controlled substance (CX) because it contains eluxadoline that can be a target for people who abuse prescription medicines or street drugs. 2  Keep your VIBERZI in a safe place, to protect it from theft.3  Never give your VIBERZI to anyone else, because it may harm them.IBERZI is a prescription medicine used to treat adults who have irritable bowel syndrome with diarrhea (IBS-D). 1  VIBERZI is a controlled substance (CX) because it contains eluxadoline that can be a target for people who abuse prescription medicines or street drugs.