Antibiotic-Associated Diarrhea

What is antibiotic-associated diarrhea?

Antibiotic-associated diarrhea is a side effect of taking antibiotic medicine. Symptoms usually start between 4 and 9 days after you start to take the medicine. Most often the loose bowel movements are mild and go away when you stop taking the antibiotic. Sometimes the diarrhea can be very severe.

How does it occur?

Antibiotics can upset the natural balance of “good” and “bad” bacteria in the bowel. Different antibiotics treat different kinds of bacteria. When an antibiotic kills one type of bacteria, you then have more of other types of bacteria in the gut. Having too much of some kinds of bacteria in the gut can cause diarrhea.

Bacteria called Clostridium difficile (or C. difficile) are a common cause of antibiotic-associated diarrhea. They can cause severe diarrhea and an infection called pseudomembranous colitis. Many people get this infection after a stay in a hospital or nursing facility.

What are the symptoms?

The main symptom of mild diarrhea is loose bowel movements or more bowel movements than normal.

Symptoms of pseudomembranous colitis are more severe and may include:

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

How is it diagnosed?

Your healthcare 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 for harmful bacteria. Your provider may examine the lining of your rectum and lower bowel.

How is it treated?

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

• Stop taking the antibiotic.
• Change your diet for a few days.

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

How long do the effects last?

In mild cases, diarrhea may last up to 14 days after you stop taking the antibiotic.

In more severe cases, the symptoms may not go away until several weeks after you start treatment. The symptoms may also come back after treatment. This is because some antibiotics have an effect on the balance of bacteria in your gut for a long time.

How can I take care of myself?

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

• Drink clear liquids, such as water, weak tea, broth, apple or grape juice, flat ginger ale, or sports drinks.
• Eat only bland foods in small amounts, such as soda crackers, toast, plain pasta, noodles, bananas, and baked or boiled potatoes.
• Avoid foods and drinks that can cause diarrhea. These foods include caffeine, alcohol, milk products, large amounts of fruit or fruit juices (except bananas), and spicy foods.

After a few days, you may return to normal eating. This means that you can carefully add back the foods that sometimes cause diarrhea.

If you have cramps or stomach pain, it may help to put a covered hot water bottle or electric heating pad on your belly. Set the heating pad on low. You should never set a heating pad on high because you could get burned.

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

Call your 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 healthcare provider feel they are necessary.
• Take antibiotics exactly as they are prescribed. Unless you are instructed otherwise by your provider, don’t increase the dose and don’t change the time between your doses. Also don’t change the number of days you take the medicine.
• When possible, avoid taking antibiotics that cause you to have diarrhea.

You can get more information from the Centers for Disease Control (CDC) at http://www.cdc.gov/ncidod/dhqp/pdf/guidelines/Cdiff_tagged.pdf.