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Antibiotic-Associated Diarrhea

What is antibiotic-associated diarrhea?

Antibiotic-associated diarrhea is a side effect of taking antibiotic medicine. Most often the diarrhea is mild and goes away when you stop taking the antibiotic. Sometimes a very serious type of diarrhea occurs called pseudomembranous colitis.

How does it occur?

Antibiotics can upset the natural balance of bacteria in the intestines. Too many harmful bacteria in the intestines can cause diarrhea.

Almost any antibiotic can cause an imbalance of bacteria in the body. Some of the most common ones are ampicillin and clindamycin.

An overgrowth of bacteria called Clostridium difficile causes the more severe diarrhea called pseudomembranous colitis.

What are the symptoms?

The main symptom of mild antibiotic-associated diarrhea is loose or frequent bowel movements.

Symptoms of pseudomembranous colitis are more severe and may include:

  • a lot of watery diarrhea (sometimes bloody)
  • abdominal pain and cramping
  • nausea
  • dehydration
  • fever.

How is it diagnosed?

Your health care provider will ask about the medicines you are taking. If your symptoms are mild, you may not need any lab tests.

If you have more severe symptoms, your provider may check a sample of bowel movement. Your provider may examine the lining of your rectum and lower bowel.

How is it treated?

If your symptoms are mild, your health care provider may recommend that you:

  • Stop taking the antibiotic.
  • Change your diet for a while.

If your symptoms are more severe, you may need bed rest, intravenous (IV) fluids, and another antibiotic to treat Clostridium bacteria.

How long do the effects last?

In mild cases, diarrhea may last up to 14 days after you stop taking the antibiotic. If you have a more severe case, the symptoms may not go away until several weeks after you begin treatment.

Sometimes the symptoms return in spite of treatment.

How can I take care of myself?

Follow your health care provider's instructions for rest, activity, medicine, and diet. Your provider will probably suggest that you:

  • Drink clear liquids, such as water, apple juice, tea, bouillon, and flat ginger ale.
  • Eat only bland foods in small amounts, such as soda crackers, toast, plain pasta, noodles, bananas, and baked or broiled potatoes.
  • Avoid foods and drinks that sometimes cause diarrhea. These foods include caffeine, alcohol, milk and milk products, large amounts of fruit or fruit juices (except bananas), and foods seasoned with hot peppers.
  • After a few days, you may return to normal eating, carefully adding back any of the foods that sometimes cause diarrhea.

If you have cramps or abdominal pain, it may help to put a hot water bottle or electric heating pad (set on low) on your abdomen.

If your health care provider prescribes a new antibiotic, take all of the medicine as prescribed.

Call your health care provider if:

  • Your pain does not go away or gets worse.
  • Your diarrhea or other symptoms get worse.

What can I do to help prevent antibiotic-associated diarrhea?

  • Take antibiotics only when you and your health care provider feel they are necessary.
  • Take antibiotics exactly as they are prescribed. Do not increase the dose, the time between your doses, or the number of days you take the medicine unless instructed to do so by your health care provider.
  • When possible, avoid taking antibiotics that cause you to have these symptoms.
Developed by McKesson Health Solutions LLC.
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright © 2003 McKesson Health Solutions LLC. All rights reserved.
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