Diarrhea from Medication


All medicines carry a small risk of side effects and some people may experience diarrhea as a result of taking certain medication.

Antibiotics and diarrhea

While a number of medicines can cause diarrhea, antibiotics are most commonly to blame for upset stomach

This is because they not only kill the ‘bad’ bacteria responsible for infection, but they destroy the ‘good’ bacteria that also live in the gut. This changes the composition of our gut flora or intestinal flora, reducing the intestine’s ability to absorb fatty acids and other essential nutrients, it weakens the gastrointestinal barrier and the immune system and thus can lead to diarrhea.

At the same time, the change in gut flora can increase its vulnerability to aggressive pathogen bacteria living inside the intestine, which can lead to an infection and diarrhea.

You can help protect your gut flora by taking extra probiotics to top up your level of good live bacteria, when you’re next on medication. Find out about this in our Managing Your Diarrhea area.

Here are some medications that can sometimes cause diarrhea:

  • Antibiotics
  • Antacid medicines containing magnesium
  • Some chemotherapy medicines
  • Non-steroid anti-inflammatory drugs (NSAIDs)
  • Selective serotonin reuptake inhibitors (SSRIs)
  • Statins (cholesterol-lowering medicines) 
  • Laxatives (medicines used to help empty your bowels) 

How to treat diarrhea

If you get diarrhea while taking a course of medication, you should treat it straight away. IMODIUM® works in harmony with your body to help restore its natural rhythm and resume the normal pace of the digestive system. It’s best to act quickly to limit the further loss of fluids and salts and avoid becoming dehydrated, as this can leave you feeling even more ill and drained. After all, if you’re unwell or have an infection, diarrhea is the last thing you need.

Find out more about Diarrhea Treatments

IMODIUM® Capsules are proven and trusted for stopping diarrhea.

IMODIUM® Instants dissolve instantly on your tongue, so they’re perfect for when you’re on the go.

Where to buy IMODIUM®

It’s easy to find IMODIUM® in pharmacies. You don’t need a prescription, so you can buy it over the counter.