Loperamide may cause serious or life-threatening changes in your heart rhythm, especially in people who have taken more than the recommended amount. Tell your doctor if have or have ever had a prolonged QT interval (a rare heart problem that may cause irregular heartbeat, fainting, or sudden death), a slow or irregular heartbeat, or a low level of potassium in your blood. Also tell your doctor if you are taking or plan to take any of the following medications: amiodarone (Nexterone, Pacerone), chlorpromazine, haloperidol (Haldol), methadone (Dolophine, Methadose), moxifloxacin (Avelox), pentamidine (Nebupent, Pentam), procainamide, quinidine (in Nuedexta), sotalol (Betapace, Betapace AF), thioridazine, and ziprasidone (Geodon). Your doctor will probably tell you not to take loperamide if you are taking any of these medications or if you have any of these conditions. If you experience any of the following symptoms while taking loperamide, call your doctor immediately or instruct a friend or caregiver to call local emergency services at 911: fast, irregular, or pounding heartbeat; dizziness; lightheadedness; unresponsiveness; or fainting.Taking more than the recommended amount of loperamide can cause heart problems that may be serious or cause death. Do not take a larger dose, take it more often, or take it for a longer period of time than prescribed by your doctor or as stated on the package.Loperamide should not be given to a child younger than 2 years of age because of the risk of serious breathing and heart problems.Why is this medication prescribed?, Loperamide is an anti-diarrheal medication used to treat diarrhea and reduce stool output in ileostomy patients by slowing intestinal movement., Loperamide, sold under the brand name Imodium, among others, [1] is a medication of the opioid receptor agonist class used to decrease the frequency of diarrhea. [5][4] It is often used for this purpose in irritable bowel syndrome, inflammatory bowel disease, short bowel syndrome, [4] Crohn's disease, and ulcerative colitis. [5].