Imodium starts to relieve diarrhea symptoms within one hour. It is available in capsule as well as regular and quick-dissolving tablet forms. Imodium is not suitable for everyone, though, including people who are younger than 12.

This article explains how Imodium works, what dose you should take depending on your age, and the side effects that can occur. It also covers who should not use Imodium, whether it is OK to use Imodium every day, and more.

What Does Imodium Do?

Imodium is a medication that is effective in reducing the symptoms of diarrhea. Specifically, Imodium works in the following ways:

Reduces the speed and frequency of colon contractions Reduces the secretion of fluid within the large intestine Increases the absorption of fluids and electrolytes into the intestinal tract Increases the transit time of stool through the colon Increases muscle tone in the anal sphincter, thus reducing the chances of a soiling accident May have no or only a limited effect in terms of reducing abdominal pain

When You Should Not Take Imodium

Do not take Imodium if you see any sign of rectal bleeding or blood in your stool. Also, avoid it if you are running a fever or have any other signs of a bacterial infection such as Clostridioides difficile (C. diff), salmonella, or E. coli.

With a bacterial infection, you don’t want to slow down the bowel because you want to help the body eliminate the infectious agent as quickly as possible.

Use by Children

Imodium is generally seen as a safe, effective remedy for the treatment of diarrhea in children over the age of 6. However, it is always a good idea to check with your child’s healthcare provider before giving them any medication, even if it is available over the counter.

Imodium would not be recommended for a child who is dehydrated, malnourished, or experiencing bloody diarrhea.

Use in Pregnancy

If you are pregnant, you should not use any medication without first getting approval from your healthcare provider.

One small study published in 2008 identified a possible link between the use of Imodium in early pregnancy and several fetal risk factors. These include hypospadias (a urethra birth defect concerning the opening of the penis), large baby size, and a higher rate of Cesarean births.

Use in Inflammatory Bowel Disease

People who have inflammatory bowel disease (IBD) should not take Imodium without permission from their healthcare provider. The use of antidiarrheal medications such as Imodium places IBD patients at risk for the development of toxic megacolon, a potentially life-threatening disorder.

Imodium Dosage

For best results, follow the dosing information on the medication packaging. A typical dose of Imodium is to take 2 milligrams (mg) twice a day.

In order to reduce the risk of the Imodium working too well and providing you with a new problem—namely, that of constipation—it is recommended that you start with a small dose, perhaps limiting yourself to 1 to 2 mg over the course of a day.

If necessary, you can increase the amount of Imodium that you take. The most you should ever take in a day is 8 mg unless your healthcare provider advises you otherwise. Be sure to drink lots of water while taking Imodium.

Imodium doesn’t stop diarrhea immediately, but you may experience symptom relief within an hour of taking the medication. It will be at its highest level of effectiveness approximately 16 to 24 hours after you take it.

Side Effects of Taking Immodium

Imodium tends to be well-tolerated and to cause minimal side effects. This is because it works primarily within the large intestine. Very little of the medication enters the bloodstream and it does not cross the blood-brain barrier, thus there is no risk of addiction.

When side effects do occur, they tend to be only digestive in nature:

Abdominal pain or crampingBloatingConstipationNauseaVomiting

A Word From Verywell

Except for precautions taken with young children, pregnant women, and those with IBD, Imodium is considered to be a relatively safe, well-tolerated option for dealing with diarrhea.

If you find that you need to take Imodium on a more frequent basis, be sure to discuss your symptoms and your dosage with your healthcare provider.