Antidiarrheal Medicines

What are antidiarrheal medicines?

Antidiarrheal medicines may be used to treat diarrhea for a short time (1 to 2 days). Diarrhea means frequent loose bowel movements. Most people have diarrhea once in a while. It may be caused by stomach flu or by eating or drinking contaminated food or water. Diarrhea can be very serious in older adults. It can cause dehydration (a loss of too much fluid from the body).

How do antidiarrheal medicines work?

There are 3 main types of antidiarrheal medicines:

• stool thickeners
• antispasmodic medicines
• bulking agents.

Stool thickeners (such as Kaopectate) absorb some bacteria and toxins in the intestines. They also thicken the stool with clay or fruit pectin. Stop taking stool thickeners as soon as they stop the diarrhea or if they do not seem to be helping after 48 hours of use.

Antispasmodic medicines (such as Imodium) slow down the passage of food and stool through the intestines. This allows time for more water to be absorbed from the stool into the intestines. This results in fewer and firmer stools.

Many antidiarrheal medicines contain both a stool thickener and an antispasmodic medicine. Long-term use of stool thickeners or antispasmodic medicines is not advised.

Bulking agents are another way to thicken the stool. They consist of natural fibers that are made from plant seeds. The fibers form a thickening gel inside the intestines. A well-known bulking agent is Metamucil.

When are they used?

You should use these medicines only when you really have to. For example, if you are traveling and have diarrhea, you may need medicine for the times when you can't get to a bathroom.

Be cautious about taking nonprescription medicines such as loperamide (Kaopectate or Imodium) or the prescription medicine Lomotil. These medicines can actually make the illness more severe. If you have a bacterial infection, diarrhea is your body's way of getting rid of the bad bacteria. With approval from your provider, take these medicines if diarrhea lasts for more than 1 or 2 days.

You should not use antidiarrheal medicine if you have:

• glaucoma
• prostate problems
• kidney or liver disease.

What should I watch out for while taking antidiarrheal medicines?

• If you have blood in the stool along with diarrhea, call your health care provider.
• Read the package label carefully for instructions, warnings, and ingredients.
• Tell your health care provider if your symptoms do not improve within 2 or 3 days, or if they get worse.
• Do not use these products for 3 or more days without seeking advice from your provider.