What Meds Cause Diarrhea?

Medically Reviewed by Minesh Khatri, MD on March 17, 2024
2 min read

Diarrhea is a common side effect of drugs, and many medications can cause it. Certain ones are frequent culprits.

Doctors don’t really understand why antibiotics cause diarrhea. They think it’s because the drugs kill bacteria that help your body digest food. Whatever the reason, just about any antibiotic can bring on diarrhea. If yours does, talk to your doctor. They may be able to give you a different one to try.

Over-the-counter medicines you take for heartburn can cause diarrhea. When they do, it can be because they contain magnesium or calcium.

If you have gastroesophageal reflux disease, or GERD, you might take a type of drug called a proton pump inhibitor (PPI). You also might take a PPI if you have an ulcer. It doesn’t happen often, but some people who take these drugs get diarrhea. Some have a version caused by a serious bacterial infection called Clostridium difficile (C. diff).

PPIs are available over-the-counter and by prescription. They include:

Diarrhea is sometimes a side effect of drugs prescribed to treat depression and mood disorders.

A group of meds called selective serotonin reuptake inhibitors, or SSRIs, is a common culprit. These are the most commonly prescribed drugs for depression. They include:

Some antidepressants are “atypical” because they work differently in your body than other classes of mood-disorder drugs. Some of them can cause diarrhea. Those include:

Lithium (Eskalith, Lithobid), another drug used to treat mood disorders, can also cause diarrhea.

Diarrhea is common among people undergoing cancer treatment. Chemotherapy drugs can change how your body breaks down food. That disrupts how your small intestine works, which can lead to diarrhea.

Researchers have linked more than 700 drugs to diarrhea. Among the ones not already mentioned are:

  • Non-steroidal anti-inflammatory drugs, or NSAIDs, which are taken to relieve swelling and pain
  • Metformin, a prescription drug that treats type 2 diabetes
  • Colchicine (Colcrys, Mitigare), a medicine prescribed for people with gout
  • Angiotensin-converting enzyme (ACE) inhibitors, a group of drugs prescribed for high blood pressure
  • Bisphosphonates, prescribed for osteoporosis
  • Magnesium supplements