What is this medication?

LOPERAMIDE (loe PER a mide) treats occasional diarrhea. It works by slowing down an overactive bowel, which decreases the number of bowel movements. It belongs to a group of medications called antidiarrheals. It is often used for a short period of time.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): Anti-Diarrheal, Imodium A-D, K-Pek II

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • A black or bloody stool
  • Bacterial food poisoning
  • Colitis or mucus in your stool
  • Currently taking an antibiotic medication for an infection
  • Fever
  • History of irregular heartbeat
  • Liver disease
  • Severe abdominal pain, swelling or bulging
  • An unusual or allergic reaction to loperamide, other medications, foods, dyes, or preservatives
  • Pregnant or trying to get pregnant
  • Breast-feeding

How should I use this medication?

Take this medication by mouth with a glass of water. Follow the directions on the prescription label. Take your doses at regular intervals. Do not take your medication more often than directed.

Talk to your care team regarding the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

This does not apply. This medication is not for regular use. Only take this medication while you continue to have loose bowel movements. Do not take more medication than recommended by the packaging label or by your care team.

What may interact with this medication?

Do not take this medication with any of the following:

  • Alosetron

This medication may also interact with the following:

  • Cimetidine
  • Clarithromycin
  • Erythromycin
  • Gemfibrozil
  • Itraconazole
  • Ketoconazole
  • Quinidine
  • Quinine
  • Ranitidine
  • Ritonavir
  • Saquinavir

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Do not take this medication for more than 2 days without asking your care team. Do not use doses higher than those prescribed by your care team or listed on the label. Check with your care team right away if you develop a fever, severe abdominal pain, swelling or bulging, or if you have bloody/black diarrhea or stools.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medication affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells. Alcohol can increase possible drowsiness and dizziness. Avoid alcoholic drinks.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your care team if the problem does not go away or is severe. Drinking plenty of water can also help prevent dehydration that can occur with diarrhea.

Elderly patients may have a more variable response to the effects of this medication, and are more susceptible to the effects of dehydration.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Heart rhythm changes—fast or irregular heartbeat, dizziness, feeling faint or lightheaded, chest pain, trouble breathing
  • Redness, blistering, peeling, or loosening of the skin, including inside the mouth
  • Severe stomach pain
  • Trouble passing urine

Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):

  • Bloating
  • Blurry vision
  • Constipation
  • Dizziness
  • Drowsiness
  • Dry mouth
  • Nausea
  • Passing gas
  • Vomiting

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store at room temperature between 15 and 25 degrees C (59 and 77 degrees F). Keep container tightly closed. Throw away any unused medication after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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