Imodium for IBS? (dose, times, safety, how to take it)

You might be asking yourself, can I take Imodium for IBS? 

Having disruptive bowel symptoms in IBS is common. Imodium can be a useful medication to relieve your diarrhea caused by IBS.

However, IBS is very individual. This post will answer some of the questions you might have about taking Imodium for IBS.

This post is for general information and interest only, it does not provide medical advice. If you require medical advice please seek this from your doctor.

What is Imodium?

Imodium is an over-the-counter antidiarrheal medication. You can buy Imodium easily in supermarkets, pharmacies or get it via prescription. 

Imodium is actually a brand name for the drug loperamide.

National clinical guidelines say that loperamide is a drug that is licensed to treat acute diarrhea in IBS in adults (1).

Other brands of loperamide include:

• Dioraleze
• Entrocalm
• Norimode

Supermarkets and pharmacies such as Boots, ASDA and Tesco have their own brand of loperamide tablets, too.

You can buy these in various forms to suit you, including:

• Capsules
• Melt on the tongue tablets
• Liquid 

It’s worth noting that some brands sold in the shops say IBS on the packaging. These are no different from the others. 

How does Imodium work?

Imodium is an antimotility drug which means it works by slowing down the pace of your gut. As a result, it takes longer for food and fluid to move through your gut.

By doing this, your gut has more time to absorb water and nutrients. This means that there’s less fluid in your gut and consequently, better formed stools – thus reducing diarrhea.

How long does Imodium take to work?

Imodium can start working an hour after taking the initial dose. If your diarrhea continues, you can take the next dose after your next bout of diarrhea.

Keep in mind that the dose may vary according to the version you have bought. Follow the instructions provided by the brand or from a registered medical professional.

How long does Imodium last?

Imodium usually works for around 8-12 hours (2). Depending on the cause of your diarrhea, you may find your diarrhea then comes back.

For example, if your diarrhea was triggered by stress which is continuing then the diarrhea will likely come back as the drug wears off.

However, if your diarrhea was triggered by a high FODMAP food which has now moved through your body then you will not continue to have symptoms.

What is the best time of day to take Imodium?

General recommendations state that after the initial dose, imodium should be taken after each bout of diarrhea, rather than at set times of the day (3).

Some studies have looked into the impact of loperamide being taken at specific times to help manage IBS (4). 

However, the results from these studies aren’t clear. There is no recommendation therefore to take loperamide at set times through the day to manage IBS.

Is it harmful to take Imodium every day? 

Many people safely take loperamide long-term. 

If you do find yourself taking loperamide for more than 2 days, you should seek advice from your GP to ensure that it’s safe for you to do so (3).

You should not take Imodium if you have certain medical conditions. These include but aren’t limited to (1): 

• Acute ulcerative colitis
• Antibiotic-associated colitis
• Bacterial enterocolitis.

The Imodium website has further details on taking Imodium for IBS, including when it’s recommended to speak to your GP.

What are the side effects of taking too much Imodium? 

Like any medication, there can be side effects of taking Imodium, which might include (3):

• Dizziness
• Tiredness
• Headache
• Nausea
• Vomiting
• Dry mouth

For a full list of side effects and precautions, have a look at the Imodium brand guidelines. 

Taking Imodium as a preventative measure for IBS may also disrupt your pelvic floor feedback system – it can ‘override’ your body’s natural signals to open your bowels. 

As such, it’s better in the long run to take it to help treat your diarrhea symptoms, rather than in advance of them. 

And even then, we recommend that you look for longer-term solutions to your diarrhea such as the low FODMAP diet process and anxiety management techniques.

We often see people feeling very anxious about having diarrhea. This means you may be tempted to take too much Imodium.

However, this may result in too much water being drawn out of the gut. This results in hard stools and the yo-yo effect of diarrhea to constipation. 

You should carefully monitor your symptoms and note how much Imodium you are taking. 

What’s more effective for diarrhea, Pepto Bismol or Imodium?

Pepto Bismol is an antidiarrheal medicine, taken in liquid form. It’s also commonly used to help with heartburn and indigestion. 

The active ingredient in Pepto Bismol is bismuth subsalicylate. Pepto Bismol works differently from Imodium – it coats your gut; protecting it from stomach acid. 

Pepto Bismol also kills certain bacteria that live in your gut which can be a cause of diarrhea.

You may find that Pepto-Bismol helps with your IBS, however some research has shown that Imodium is likely to work faster, and provide better results than Pepto Bismol for diarrhea (5). 

Summary

Taking Imodium for IBS can be helpful if you experience diarrhea as one of your symptoms.

However, if using Imodium for IBS for over 2 days you should check in with your doctor before carrying on.

Always remember that IBS is multifactorial; diet and lifestyle approaches should also be a part of your IBS management. It is recommended that you work with a specialist dietitian to help you.

Have a look at our detailed article on IBS-D and how you can manage it to find out more about what you can do to help with your symptoms.