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Loperamide - Oral

Pronunciation: low-PAIR-uh-mide

Common Brand Name(s): Diarest, Diarr-Eze, Imodium

Important: How To Use This Information

This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Warning

Improper use of this medication (overuse or abuse) may cause serious harm, such as fast/irregular heartbeat or death. Do not increase your dose, take it more often, or take it for longer than directed. Taking loperamide with certain other medications may also cause harm. See also Precautions, Drug Interactions, and Overdose sections.

This medication should not be used by children younger than 2 years due to an increased risk of side effects (such as slow/shallow breathing, fast/irregular heartbeat).

Uses

See also Warning section.

This medication is used to treat sudden diarrhea (including traveler's diarrhea). It works by slowing down the movement of the gut. This decreases the number of bowel movements and makes the stool less watery. Loperamide is also used to reduce the amount of discharge in patients who have undergone an ileostomy. It is also used to treat on-going diarrhea in people with inflammatory bowel disease.

Loperamide treats only the symptoms, not the cause of the diarrhea (such as infection). Treatment of other symptoms and the cause of the diarrhea should be determined by your doctor.

How To Use

See also Warning section.

If you are using the over-the-counter product to self-treat, read all the directions on the product package before taking this medication. If your doctor has prescribed this medication, follow your doctor's directions and the directions on your prescription label.

Take this medication by mouth, usually after each loose stool, or as directed by your doctor. The dosage is based on your condition and response to treatment. In children, dosage is also based on age and weight. Adults should not use more than 8 milligrams in 24 hours if self-treating, or 16 milligrams in 24 hours if under a doctor's direction.

If you are taking the chewable tablet, take this medication on an empty stomach. The chewable tablets should be chewed thoroughly before swallowing.

If you are using the rapidly dissolving tablets, dry your hands before opening the blister pack to carefully remove a tablet. Do not push the tablet through the blister pack. Place the tablet on the tongue, allow it to dissolve completely, then swallow it with saliva. Do not crush, split, or break the tablet before taking it. Do not remove the tablet from the blister pack until just before taking. No water is needed to take this medication.

Diarrhea can cause dehydration. Drink plenty of fluids and minerals (electrolytes) to replace what is lost. Tell your doctor right away if you develop signs of dehydration (such as extreme thirst, decreased urination, muscle cramps, weakness, fainting). You may also need to change to a bland diet during this time to reduce irritation to your stomach/intestines. Consult your doctor or pharmacist for more information.

Tell your doctor if your diarrhea does not improve after 2 days, if your condition worsens, or if you develop new symptoms. If you develop blood in the stool, fever, or an uncomfortable fullness/swelling of the stomach/abdomen, or if you think you may have a serious medical problem, get medical help right away.

If you are taking this medication under your doctor's direction for ongoing diarrhea, tell your doctor if your diarrhea continues after 10 days of treatment.

Side Effects

Dizziness, drowsiness, tiredness, or constipation may occur. If any of these effects last or get worse, tell your doctor promptly.

If your doctor has prescribed this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Stop taking this medication and get medical help right away if you have any very serious side effects, including:

  • severe constipation/nausea/vomiting
  • stomach/abdominal pain
  • uncomfortable fullness of the stomach/abdomen
  • fast/irregular heartbeat
  • severe dizziness
  • fainting

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking loperamide, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

If you have any of the following health problems, consult your doctor or pharmacist before using this medication:

  • stomach/abdominal pain without diarrhea
  • bowel obstruction (such as ileus, megacolon, abdominal distention)
  • black/tarry stool
  • blood/mucus in your stool
  • high fever
  • HIV infection/AIDS
  • liver problems
  • certain stomach/intestinal infections (such as Salmonella, Shigella)
  • certain type of bowel disease (acute ulcerative colitis)

The rapidly dissolving tablets may contain aspartame or phenylalanine. If you have phenylketonuria (PKU) or any other condition that requires you to restrict your intake of aspartame or phenylalanine, consult your doctor or pharmacist regarding the safe use of this medicine.

Antibiotics may rarely cause a severe intestinal condition due to a bacteria called C. difficile. Symptoms include: diarrhea that doesn't stop, abdominal or stomach pain/cramping, or blood/mucus in your stool. This condition may occur during treatment or weeks to months after treatment has stopped. This medication may make this condition worse. Do not use this anti-diarrhea product, especially after recent antibiotic use, if you have the above symptoms without talking with your doctor first.

Loperamide may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.

The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using loperamide, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions:

  • certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG)
  • family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death)

Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using loperamide safely.

This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Older adults may be more sensitive to the side effects of this drug, especially QT prolongation (see above).

Children may be more sensitive to the side effects of this drug, especially drowsiness. Children are also at a higher risk for dehydration. See also Warning and How to Use sections.

During pregnancy, this medication should be used only if clearly needed. Discuss the risks and benefits with your doctor.

This drug passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.

Drug Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include:

  • pramlintide
  • recent/current antibiotic use
  • cholestyramine
  • ritonavir
  • saquinavir

Many drugs besides loperamide may affect the heart rhythm (QT prolongation), including amiodarone, chlorpromazine, haloperidol, methadone, moxifloxacin, pentamidine, procainamide, quinidine, sotalol, thioridazine, ziprasidone, among others.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center. Symptoms of overdose may include: difficult urination, slowed breathing, deep sleep, fast/irregular heartbeat, severe dizziness, fainting.

Notes

If your doctor has prescribed this medication for you, do not share it with others.

Missed Dose

If you are taking this drug on a regular schedule (not "as needed") and you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

If you have questions about missing a dose or you don't have more medication, contact your healthcare provider or pharmacist.

Storage

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

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