Loperamide

Loperamide is a medication used to control symptoms of diarrhea.

Loperamide belongs to a group of drugs called anti-diarrheals. These work by slowing the muscle contractions in the small intestines and in turn increase the time it takes food to pass through the gastrointestinal tract. This then gives the small intestine more time to absorb fluid and nutrients from food to make stools more firm and less often.

Loperamide can cause nausea and stomach cramps. Loperamide can also cause tiredness, drowsiness, or dizziness. Do not drive or operate heavy machinery until you know how loperamide affects you.

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop taking loperamide and call your doctor at once if you have:

• headache with chest pain and severe dizziness;

• a light-headed feeling, like you might pass out;

• fast or pounding heartbeats;

• stomach pain or bloating;

• ongoing or worsening diarrhea;

• diarrhea that is watery or bloody; or

• severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common side effects may include:

• dizziness, drowsiness;

• dry mouth;

• constipation;

• stomach discomfort; or

• nausea and vomiting.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Usual Adult Dose for Diarrhea -- Acute:

Tablets, capsules, and liquid:
Initial: 4 mg orally after the first loose stool, then
Maintenance: 2 mg after each loose stool, not to exceed 16 mg in any 24-hour period. Clinical improvement is usually observed within 48 hours.
Chewable tablets:
Initial: 4 mg after the first loose stool, then
Maintenance: 2 mg after each subsequent loose stool, but not exceeding 8 mg in 24 hours.

Usual Adult Dose for Diarrhea -- Chronic:

Tablets, capsules, and liquid:
Initial: 4 mg orally once followed by 2 mg orally after each loose stool, not to exceed 16 mg in any 24-hour period.
Maintenance: The average daily maintenance dosage is 4 to 8 mg. Clinical improvement is usually observed within 10 days. If clinical improvement is not observed at a maximum dosage of 16 mg for duration of 10 days, symptoms are unlikely to be controlled by further administration.

Usual Pediatric Dose for Diarrhea -- Acute:

2 to 6 years (13 to 20 kg):
Liquid formulation only to be used in this age group.
Initial: 1 mg orally 3 times a day for the first day, then
Maintenance: 0.1 mg/kg/dose after each loose stool, but not exceeding initial dose.

6 to 8 years (20 to 30 kg):
Tablets, capsules, and liquid:
Initial: 2 mg orally twice a day for the first day, then
Maintenance: 0.1 mg/kg/dose after each loose stool, but not exceeding initial dose.
Chewable tablets:
Initial: 2 mg orally after the first loose stool, then
Maintenance: 1 mg orally after each subsequent loose stool, but not exceeding 4 mg in 24 hours.

8 to 12 years (greater than 30 kg):
Tablets, capsules, and liquid:
Initial: 2 mg orally 3 times a day for the first day, then
Maintenance: 0.1 mg/kg/dose after each loose stool, but not exceeding initial dose.
Chewable tablets:
Initial: 2 mg orally after the first loose stool, then
Maintenance: 1 mg orally after each subsequent loose stool, but not exceeding 6 mg in 24 hours.

12 to 18 years:
Tablets, chewable tablets, capsules, and liquid:
Initial: 4 mg after the first loose stool, then
Maintenance: 2 mg after each subsequent loose stool, but not exceeding 8 mg in 24 hours.

Usual Pediatric Dose for Diarrhea -- Chronic:

less than 2 years:
Therapeutic dose for the treatment of chronic diarrhea has not been established for this patient population.

In the U.S.

• Diamode
• Imodium
• Imodium A-D
• Imogen
• Imotil
• Imperim
• Kaodene A-D
• Kao-Paverin Caps

Available Dosage Forms:

• Tablet
• Capsule
• Liquid
• Tablet, Chewable
• Solution
• Capsule, Liquid Filled
• Suspension

Therapeutic Class: Antidiarrheal

Do not use loperamide to treat your diarrhea if you have a fever or if there is blood or mucus in your stools. Contact your doctor.

For safe and effective use of loperamide:

• Follow your doctor's instructions if loperamide was prescribed.
• Follow the manufacturer's package directions if you are treating yourself.

Use a specially marked measuring spoon or other device to measure each dose accurately. The average household teaspoon may not hold the right amount of liquid.

Importance of diet and fluid intake while treating diarrhea:

• In addition to using medicine for diarrhea, it is very important that you replace the fluid lost by the body and follow a proper diet. For the first 24 hours, you should eat gelatin, and drink plenty of caffeine-free clear liquids, such as ginger ale, decaffeinated cola, decaffeinated tea, and broth. During the next 24 hours you may eat bland foods, such as cooked cereals, bread, crackers, and applesauce. Fruits, vegetables, fried or spicy foods, bran, candy, caffeine, and alcoholic beverages may make the condition worse.
• If too much fluid has been lost by the body due to the diarrhea, a serious condition (dehydration) may develop. Check with your doctor as soon as possible if any of the following signs or symptoms of too much fluid loss occur:
  • Decreased urination
  • Dizziness and lightheadedness
  • Dryness of mouth
  • Increased thirst
  • Wrinkled skin

Dosing

The dose of loperamide will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of loperamide. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

• For diarrhea:
  • For oral dosage form (capsules):
    • Adults and teenagers—The usual dose is 4 milligrams (mg) (2 capsules) after the first loose bowel movement, and 2 mg (1 capsule) after each loose bowel movement after the first dose has been taken. No more than 16 mg (8 capsules) should be taken in any twenty-four-hour period.
    • Children 8 to 12 years of age—The usual dose is 2 mg (1 capsule) three times a day.
    • Children 6 to 8 years of age—The usual dose is 2 mg (1 capsule) two times a day.
    • Children up to 6 years of age—Use is not recommended unless directed by your doctor.
  • For oral dosage form (oral solution):
    • Adults and teenagers—The usual dose is 4 teaspoonfuls (4 mg) after the first loose bowel movement, and 2 teaspoonfuls (2 mg) after each loose bowel movement after the first dose has been taken. No more than 8 teaspoonfuls (8 mg) should be taken in any twenty-four-hour period.
    • Children 9 to 11 years of age—The usual dose is 2 teaspoonfuls (2 mg) after the first loose bowel movement, and 1 teaspoonful (1 mg) after each loose bowel movement after the first dose has been taken. No more than 6 teaspoonfuls (6 mg) should be taken in any twenty-four-hour period.
    • Children 6 to 8 years of age—The usual dose is 2 teaspoonfuls (2 mg) after the first loose bowel movement, and 1 teaspoonful (1 mg) after each loose bowel movement after the first dose has been taken. No more than 4 teaspoonfuls (4 mg) should be taken in any twenty-four-hour period.
    • Children up to 6 years of age—Use is not recommended unless directed by your doctor.
  • For oral dosage form (tablets):
    • Adults and teenagers—The usual dose is 4 mg (2 tablets) after the first loose bowel movement, and 2 mg (1 tablet) after each loose bowel movement after the first dose has been taken. No more than 8 mg (4 tablets) should be taken in any twenty-four-hour period.
    • Children 9 to 11 years of age—The usual dose is 2 mg (1 tablet) after the first loose bowel movement, and 1 mg (½ tablet) after each loose bowel movement after the first dose has been taken. No more than 6 mg (3 tablets) should be taken in any twenty-four-hour period.
    • Children 6 to 8 years of age—The usual dose is 2 mg (1 tablet) after the first loose bowel movement, and 1 mg (½ tablet) after each loose bowel movement after the first dose has been taken. No more than 4 mg (2 tablets) should be taken in any twenty-four-hour period.
    • Children up to 6 years of age—Use is not recommended unless directed by your doctor.

Missed Dose

If you miss a dose of loperamide, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Loperamide should not be used for more than 2 days, unless directed by your doctor. If you will be taking loperamide regularly for a long time, your doctor should check your progress at regular visits.

Check with your doctor if your diarrhea does not stop after two days or if you develop a fever.

In vitro and animal studies show that Loperamide hydrochloride acts by slowing intestinal motility and by affecting water and electrolyte movement through the bowel. Loperamide binds to the opiate receptor in the gut wall. Consequently, it inhibits the release of acetylcholine and prostaglandins, thereby reducing peristalsis, and increasing intestinal transit time. Loperamide increases the tone of the anal sphincter, thereby reducing incontinence and urgency.

In man, Loperamide hydrochloride prolongs the transit time of the intestinal contents. It reduces the daily fecal volume, increases the viscosity and bulk density, and diminishes the loss of fluid and electrolytes. Tolerance to the antidiarrheal effect has not been observed. Clinical studies have indicated that the apparent elimination half-life of Loperamide in man is 10.8 hours with a range of 9.1 to 14.4 hours. Plasma levels of unchanged drug remain below 2 nanograms per mL after the intake of a 2 mg capsule of Loperamide hydrochloride. Plasma levels are highest approximately 5 hours after administration of the capsule and 2.5 hours after the liquid. The peak plasma levels of Loperamide were similar for both formulations. Elimination of Loperamide mainly occurs by oxidative N-demethylation. Cytochrome P450 (CYP450) isozymes, CYP2C8 and CYP3A4, are thought to play an important role in Loperamide N-demethylation process since quercetin (CYP2C8 inhibitor) and ketoconazole (CYP3A4 inhibitor) significantly inhibited the N-demethylation process in vitro by 40% and 90%, respectively. In addition, CYP2B6 and CYP2D6 appear to play a minor role in Loperamide N-demethylation. Excretion of the unchanged Loperamide and its metabolites mainly occurs through the feces. In those patients in whom biochemical and hematological parameters were monitored during clinical trials, no trends toward abnormality during Loperamide hydrochloride therapy were noted. Similarly, urinalyses, EKG and clinical ophthalmological examinations did not show trends toward abnormality.

Diarrhea:

Rx labeling: Control and symptomatic relief of chronic diarrhea associated with inflammatory bowel disease in adults; acute nonspecific diarrhea in patients ≥2 years; to reduce volume of ileostomy discharge

OTC labeling: Control of symptoms of diarrhea, including Traveler's diarrhea

Traveler’s diarrhea

The American College of Gastroenterology recommends adjunctive loperamide therapy in patients receiving antibiotics for Traveler’s diarrhea to decrease duration of diarrhea and increase chance for a cure [Riddle 2016].

Cancer treatment-induced diarrhea

The National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology, Palliative Care, recommends the use of loperamide as palliative care in cancer treatment-induced diarrhea [Morturano 2012], [NCCN Palliative Care Guidelines Siegel 2017].

Administer with plenty of clear fluids to prevent dehydration.

Chewable tablets: Administer on an empty stomach (1 hour before or 2 hours after a meal).

Oral solution: Shake well before administering dose.