Antidiarrheal Medicines

What are antidiarrheal medicines?

Antidiarrheal medicines are used to decrease the number of diarrheal stools or to stop diarrhea. Diarrhea means frequent loose bowel movements (stools). 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). Antidiarrheal medicines may be used to treat diarrhea for a short time (1 to 2 days).

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. You should stop taking stool thickeners as soon as they stop the diarrhea, or after 2 days of use if they do not seem to be helping.

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 stools 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 because they can cause severe constipation when they are overused.

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. If your diarrhea is lasting more than 2 days, ask your healthcare provider if you need to be checked or if it is okay to use antidiarrheal medicines and if so, for how long.

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?

Read the package label carefully for instructions, warnings, and ingredients. Do not use these products for more than 2 days without seeking advice from your provider.

Call your healthcare provider if:

• You have blood in your stools along with diarrhea.
• You have a fever of 101°F (38.3°C) or higher with diarrhea.
• You have vomiting with your diarrhea and are unable to keep any liquids down for 24 hours.
• Your symptoms do not get better within 2 or 3 days, or they get worse.