If allergic to Loperamide or any ingredient in the product; If it is for a child under 12 years old; If pregnant or breastfeeding; If constipated and also in whom constipation should be avoided (e.g., diarrhea resulting from infections); If abdomen is swollen or you have abdominal pain; If with acute dysentery which is characterized by blood in stools and, high fever; If with pseudomembranous colitis (diarrhea associated with antibiotics) active ulcerative colitis, meningitis, or a history of liver disease.