AUDIENCE: Pharmacy, Cardiology, Internal Medicine, Pain Management, Consumer
ISSUE: FDA is warning that taking higher than recommended doses of the common over-the-counter (OTC) and prescription diarrhea medicine loperamide (Imodium), including through abuse or misuse of the product, can cause serious heart problems that can lead to death. The risk of these serious heart problems, including abnormal heart rhythms, may also be increased when high doses of loperamide are taken with several kinds of medicines that interact with loperamide (see Examples of Drugs that Can Potentially Interact with Loperamide, in the FDA Drug Safety Communication at: http://www.fda.gov/Drugs/DrugSafety/ucm504617.htm).
The majority of reported serious heart problems occurred in individuals who were intentionally misusing and abusing high doses of loperamide in attempts to self-treat opioid withdrawal symptoms or to achieve a feeling of euphoria. FDA continues to evaluate this safety issue and will determine if additional FDA actions are needed.
BACKGROUND: Loperamide is approved to help control symptoms of diarrhea, including Travelers' Diarrhea. The maximum approved daily dose for adults is 8 mg per day for OTC use and 16 mg per day for prescription use. It is sold under the OTC brand name Imodium A-D, as store brands, and as generics. See the FDA Drug Safety Communication at: http://www.fda.gov/Drugs/DrugSafety/ucm504617.htm for data summary.
RECOMMENDATION: Health care professionals should be aware that use of higher than recommended doses of loperamide can result in serious cardiac adverse events. Consider loperamide as a possible cause of unexplained cardiac events including QT interval prolongation, Torsades de Pointes or other ventricular arrhythmias, syncope, and cardiac arrest. In cases of abuse, individuals often use other drugs together with loperamide in attempts to increase its absorption and penetration across the blood-brain barrier, inhibit loperamide metabolism, and enhance its euphoric effects. If loperamide toxicity is suspected, promptly discontinue the drug and start necessary therapy. If loperamide ingestion is suspected, measure blood levels, which may require specific testing. For some cases of Torsades de Pointes in which drug treatment is ineffective, electrical pacing or cardioversion may be required. Refer patients with opioid use disorders for treatment (see Additional Information for Health Care Professionalsin the FDA Drug Safety Communication at: http://www.fda.gov/Drugs/DrugSafety/ucm504617.htm).
Patients and consumers should only take loperamide in the dose directed by their health care professionals or according to the OTC Drug Facts label. Do not use more than the dose prescribed or listed on the label, as doing so can cause severe heart rhythm problems or death.
If your diarrhea lasts more than 2 days, stop taking loperamide and contact your health care professional. Seek medical attention immediately by calling 911 if you or someone taking loperamide experiences any of the following:
- Rapid heartbeat or irregular heart rhythm
- Unresponsiveness, meaning that you can't wake the person up or the person doesn't answer or react normally
For more information visit the FDA website at: http://www.fda.gov/Safety/MedWatch/SafetyInformation and http://www.fda.gov/Drugs/DrugSafety.
Why is this medication prescribed?
Loperamide is used to control diarrhea. It is available with or without a prescription.
This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.
How should this medicine be used?
Loperamide comes as a tablet, capsule, and liquid to take by mouth. It usually is taken immediately after each loose bowel movement; it is sometimes taken on a schedule (one or more times a day) for chronic diarrhea. Follow the directions on the package or on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take loperamide exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
If your symptoms do not improve within 2 days (10 days for chronic diarrhea) or if you develop a fever or bloody stools, call your doctor. Drink plenty of water or other beverages to replace fluids lost while having diarrhea.
What special precautions should I follow?
Before taking loperamide,
- tell your doctor and pharmacist if you are allergic to loperamide or any other drugs.
- tell your doctor and pharmacist what prescription and nonprescription medications you are taking.
- tell your doctor or pharmacist if you have a fever.
- tell your doctor and pharmacist if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking loperamide, call your doctor.
- you should know that this drug may make you drowsy and dizzy. Do not drive a car or operate machinery until you know how this drug affects you.
- remember that alcohol can add to the drowsiness caused by this drug.
What should I do if I forget a dose?
If you are taking scheduled doses of loperamide, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.
What side effects can this medication cause?
Loperamide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- dry mouth
- stomach pain, discomfort, or distention (enlargement)
If you experience any of the following symptoms, call your doctor immediately:
- skin rash
- difficulty breathing
If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).
What should I know about storage and disposal of this medication?
Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away any medication that is outdated or no longer needed. Talk to your pharmacist about the proper disposal of your medication.
What other information should I know?
Ask your pharmacist any questions you have about taking this medicine.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
- Imodium® AD
- K-Pek II®
- Kaopectate 1-D®
- Maalox® Anti-Diarrheal
- Pepto® Diarrhea Control
Brand names of combination products
- Imodium® Advanced (containing Loperamide, Simethicone)