Imodium For Diarrhea: Indications, Dose, Side Effects, & Contraindications.

Our content is not intended nor recommended as a substitute for medical advice by your doctor. Use for informational purposes only.

What is Imodium?

Imodium is a drug used for diarrhea disease. It is available over the counter without a medical prescription.

It is minimally absorbed into the bloodstream, making it a safe option to control diarrhea associated with infection and other diseases such as Irritable bowel syndrome.


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What Imodium to take for diarrhea?

The active ingredient of Imodium is Loperamide Hydrochloride. It comes in different formulations, doses, and additives.

The best type of Imodium for diarrhea depends on age, associated symptoms, and personal preferences. Imodium A-D Caplets and soft gels are suitable for adults with diarrhea and no significant cramps and gas.

On the other hand, Imodium Multi-Symptom relief is best used for diarrhea associated with cramps, gas, and bloating. Imodium.

The table below summarizes the types of Imodium products, their components, and best-use conditions.

Imodium FormulaCompositionBest For
Caplets (tablet)Loperamide HCL (2mg).Adults with diarrhea and no gas and cramps.
SoftgelsLoperamide HCL (2mg)Adults with diarrhea who don’t like to swallow big tablets.
Multi-symptom Relief (tablets or caplets)Loperamide HCL (2mg) And SimethiconeDiarrhea associated with gas, bloating, and cramps in adults.
Oral SolutionsLoperamide HCL (1mg/7.5ml)Adults and children with diarrhea

When to take Imodium for Diarrhea? (Indications).

  • Acute infectious diarrhea.
  • Traveler’s diarrhea.
  • Cancer treatment-induced diarrhea.
  • Chronic diarrhea due to irritable bowel syndrome (IBS).
  • Chronic diarrhea due to Inflammatory bowel disease (IBD).
  • Chronic diarrhea due to other conditions, such as short-bowel syndrome, chronic non-specific diarrhea, etc.

DO NOT use Imodium for:

  • Dysentery (high fever, mucus, and bloody stools).
  • Passing black diarrhea (melena).
  • Abdominal pain without diarrhea.
  • Acute ulcerative colitis with bloody and mucus discharge.
  • Pseudomembranous colitis (antibiotic-associated bloody diarrhea).
  • Children less than two years old.
  • In those who have an allergy to Loperamide (rare).
  • Diarrhea that is not responding to Imodium for two days.

Also, Consult your doctor before taking Imodium if you are:

  • Pregnant
  • Breastfeeding
  • Taking antibiotics
  • Having high-grade fever
  • Liver cirrhosis
  • Serious heart problems.
  • Taking other medications such as Desmopressin, Haloperidol, Eluxadonline, or any other medications.

Dose and instructions.

1. Adults, Acute diarrhea:

  • 4 mg (two caplets or two Softgels) after the first attack of diarrhea or loose stool.
  • Then, 2 mg after every attack of diarrhea or loose stool.
  • The maximum daily dose is 16 gm per day (8 caplets).

2. Adults, Chronic diarrhea:

  • At first, 4 mg (two caplets or two Softgels) after the first loose bowel movement.
  • Then, 2 mg after every loose stool or diarrhea (maximum of 16 mg daily).
  • Once diarrhea is controlled, use the lowest dose to control symptoms (usually 2-4 caplets per day).
  • Don’t use it for extended periods without medical permission.
  • Note: if you are an IBS sufferer with alternating diarrhea and constipation, use Imodium for diarrhea for the shortest possible period (for fear of triggering constipation).

3. Children, acute diarrhea:

  • Age <2 years: Use of Imodium for diarrhea is CONTRAINDICATED.
  • 2-5 years (weight 13-20 kg): 1 mg (one teaspoonful of the oral solution) after every loose stool or diarrhea (Maximum 3 mg per day).
  • 6-8 years (weight 12-26 kg): Intital 2 mg, followed by 1 mg after every loose stool or diarrhea (maximum 4 mg per day).
  • 9-11 years (27-43 kg): initial 2 mg, followed by 1 mg after every loose stool or diarrhea attack (maximum 6 mg per day).
  • Children aged 12 years or more: initial 4 mg (two caplets), then 2 mg after each attack of diarrhea or loose stool (maximum 8 mg per day).

4. Children, chronic diarrhea.

  • Limited data for the use of Imodium in young children suffering from chronic diarrhea due to diseases such as short-bowel syndrome.
  • Your doctor may recommend doses of 0.08-0.24 mg/kg/day. Your doctor may also recommend its use in ages younger than two years old.
  • So, Don’t use Imodium for your child with chronic diarrhea as an OTC. Only use it under medical supervision.

Tips when you are taking Imodium for diarrhea:

  • Take Imodium for diarrhea with plenty of fluids to avoid dehydration.
  • Swallow the caplets as a whole. Don’t crush or chew it.
  • Stop taking Imodium if severe dizziness or drowsiness develops.

Side effects of Imodium for diarrhea.

  • Constipation: in about 3% of the cases (range is 2-5%).
  • Dizziness (use with caution in the elderly): in about 1% of the cases.
  • Rare:
    • Bloating.
    • Anorexia (loss of appetite).
    • Stomach pain.
    • Nausea.
    • Vomiting.
  • Very rare:
    • Severe allergic reaction (anaphylactic shock).
    • Skin rash and angioedema.
    • Dyspepsia (indigestion).
    • Fatigue.
    • Megacolon.
    • Paralytic ileus.
    • Skin rash.
    • Pruritis.
    • Steven-Jhonson syndrome.
    • Urinary retention.
    • Dry mouth (xerostomia).

How does Imodium work for diarrhea?

The active ingredient of Imodium is Loperamide. It acts on a specific type of receptors inside your gut lining called the opioid receptors.

Imodium works for diarrhea by slowing down your gut motility. To understand how Imodium works for diarrhea, you should understand how diarrhea occurs.

Your food enters your stomach and then passes into the small intestine and the colon. In the intestine, most water and nutrients are absorbed as the food and fluids move slowly through the gut.

When there is diarrhea, The intestine, and the colon contract more frequently, propelling the food and fluid content more rapidly. When gut contents move rapidly in the intestine and the colon, they will NOT have enough time to be absorbed (especially water).

The rapid transit time will make the stool loose or even watery and pass in large amounts.

What Imodium does is:

  • It decreases the contractions (peristaltic movement) of the intestine and the colon.
  • As a result, the already shortened transit time increases again.
  • So, food and water will have enough time to be absorbed.
  • And the stool returned to its normal semi-hard state instead of the loose or watery consistency.

Although Imodium works for diarrhea, it has minimal effects on abdominal pain, and it is not suitable for controlling abdominal cramps in conditions such as gastroenteritis or IBS.


Imodium works for diarrhea by decreasing the rapid motility of the gut that is causing diarrhea. This will allow the absorption of water from the gut and improve the stool form.

How long does it take for Imodium to take to work for diarrhea?

The average time it takes for Imodium to work for diarrhea is about one hour. So, Imodium is considered a rapidly-acting medication for diarrhea relief.

However, some people may need additional doses if another attack of diarrhea develops after the initial dose.


Can I take Imodium for Covid-19 diarrhea?

You can use Imodium for watery diarrhea caused by Covid-19 infection. Imodium can be used as an initial dose of 4 mg (two caplets) followed by 2 mg after every loose or watery bowel motion. Don’t exceed 16 mg per day.

Don’t take Imodium if you have bloody diarrhea with covid-19. Bloody diarrhea with Covid-19 can be due to Clostridium difficile infection (a complication of using antibiotics during Covid-19).

How long can you take Imodium for diarrhea?

For acute diarrhea, don’t take Imodium for more than two days, even if there is no response. Consult your doctor if Imodium is not working for two days.

For chronic diarrhea, your doctor may prescribe Imodium on demand or continuously. The maintenance dose is usually low (1-4 caplets per day). However, don’t take Imodium long-term without medical permission.

What to do if Imodium is not working for diarrhea?

If Imodium is not working for diarrhea, the first thing to do is to ensure you take the right dose of Imodium (initial two caplets, then one caplet after each attack of diarrhea, with a maximum of 8 caplets per day).

Stop taking Imodium If it is not working for diarrhea for two days (despite taking the maximum dose). And talk to your doctor about the best option to control diarrhea.

Does Imodium work for diarrhea and stomach cramps?

Imodium (loperamide) works for diarrhea, but it is not effective against stomach cramps. However, a combination of Loperamide and Simethicone (Imodium® Multisymptom Relief) may be effective in treating diarrhea and stomach cramps.

But you may need an antispasmodic medication to control abdominal cramps as the Imodium® multi-symptom relief is also not suitable for severe cramps.

Does Imodium work for diarrhea and vomiting?

Imodium works for diarrhea but is not effective in the prevention of vomiting. You must take another antiemetic medication or talk to your doctor about vomiting.

Also, you may use Pepto-Bismol instead of Imodium, as it can work for both vomiting and diarrhea.