Dealing with Diarrhea When You're HIV-Positive

Just about everyone - HIV-positive or negative - has diarrhea at one time or another. A brief, mild case of diarrhea may be little more than a nuisance. In contrast, chronic (long-lasting), severe diarrhea can lead to serious health problems. I recently spoke with HIV specialist Dr. Calvin Cohen about the different things that can cause or contribute to diarrhea in persons living with HIV. We also discussed the steps that people can take to avoid or control this problem.

Question: Let's start with a basic question: What exactly is diarrhea?
CC: Essentially, diarrhea means having loose, watery stools. People with diarrhea often have more than three loose bowel movements a day. Acute (short-lasting) diarrhea is very common. It typically lasts a day or two and may disappear on its own without treatment. However, severe or persistent diarrhea can lead to serious health problems, such as dehydration -- an excessive loss of fluid from the body. Severe diarrhea can also keep the body from properly absorbing nutrients and medications. Fortunately, there are many things we can do to prevent diarrhea from causing major health problems.

Question: What are the different causes of diarrhea?
CC: Many different germs can cause diarrhea. These include gastrointestinal (GI) viruses, and the bacteria and parasites that cause food poisoning and traveler's diarrhea. Eating raw shellfish, undercooked meat, contaminated vegetables, or improperly stored food may lead to illness. Amoeba infections and the parasite giardia are fairly common causes of diarrhea in both HIV-infected and uninfected persons. These may come from contaminated food and water. They may also be transmitted sexually.

You may be surprised to hear that taking antibiotics can sometimes lead to diarrhea. The reason is that these drugs may kill not only dangerous germs but also the "good" bacteria that help keep your GI tract healthy. Diarrhea may also be the result of sensitivity to particular foods, such as milk or wheat products. For example, many African Americans, Asian Americans, and Native Americans are lactose intolerant. They have difficulty digesting a substance called lactose, which is found in milk products and some medications. Other possible causes of diarrhea include pancreas problems and emotional stress.

Question: The things you've mentioned so far relate to diarrhea in anyone, whether HIV-positive or negative. Are there any other causes of, or concerns about, diarrhea particularly in HIV-infected persons?
CC: Yes. People with weakened immune systems may have more difficulty fighting off and recovering from some common GI infections. In addition, when a person's CD4 T-cell count is very low -- typically 100 or less -- they may develop diarrhea from certain opportunistic illnesses (OIs). These include the parasites cryptosporidium and microsporidium and the cytomegalovirus (CMV).

The HIV virus itself can also increase the risk of diarrhea. HIV attacks the lymph nodes of the intestines. This may lead to a condition known as HIV enteropathy, which can result in diarrhea and other GI symptoms.

Some HIV meds and drugs used to prevent or treat OIs can also cause diarrhea. These include the protease inhibitors nelfinavir (trade name Viracept), ritonavir (Norvir), and Kaletra (lopinavir + ritonavir). [Fortunately, this has become less of an issue with the newer tablet form of Kaletra.] Diarrhea and other GI side effects such as nausea often improve as the body becomes accustomed to the meds.

Question: What can people do to avoid diarrhea?
CC: There are a number of things you can do. You can wash raw fruits and vegetables thoroughly, avoid raw or undercooked meat and shellfish, and prepare and store food carefully. Practicing safer sex can avoid sexual transmission of some germs that may cause diarrhea.

If you are sensitive to milk or wheat products, you can avoid, or limit your intake of, these foods. It's worth noting that some people who are lactose intolerant are able to consume small amounts of lactose without problem. For example, they may be able to eat some aged cheeses that are quite low in lactose. Lactose-reduced milk and lactase enzyme supplements are also available in many supermarkets.

Question: How do doctors find the cause of diarrhea?
CC: The first step is to take a medical history. Your doctor will ask about any medical issues that might cause or contribute to the diarrhea. They will also want to know how long the diarrhea has gone on, the number of bowel movements you're having each day, and what these are like. Your doctor will also ask about your normal bowel habits to see how these compare to your bout of diarrhea.

In addition, your doctor will want to know about your eating habits. In particular, they will be interested in any food sensitivities and whether you might recently have been exposed to unsafe food. They should also take a sexual history to learn whether you might have been exposed to a sexually transmitted infection that can cause diarrhea. If they don't already know, your doctor may also ask for a list of everything you take. This would include all prescription medications, over-the-counter drugs, and nutritional supplements, as well as any street drugs. They will ask whether you are taking medications at the right dose and time, as directed.

If your medical history points to a likely cause of diarrhea, your doctor might immediately give you tips for managing diarrhea or prescribe a treatment. At times, however, additional steps are needed to identify the cause of diarrhea. If food sensitivity is suspected, your doctor might ask you to try eliminating certain foods from your diet to see if there's any improvement.

Your doctor may ask you to provide one or more stool samples, which can be studied for germs, parasites, blood, or mucus. They might also request that a procedure called a flexible sigmoidoscopy be done. This involves inserting a flexible tube into the rectum and then using a camera to observe the lower part of the colon. The instrument can also take colon samples for testing.

Question: How is diarrhea treated or controlled?
CC: The answer depends on the cause. As mentioned earlier, food-sensitive persons can avoid any foods that cause or contribute to diarrhea. If diarrhea is the result of an infection, then treating that infection should help. This includes providing appropriate treatment for HIV and any OIs.

If diarrhea occurs as a drug side effect, it is sometimes possible to control the problem by changing the dosage of drugs, like ritonavir, that can cause diarrhea. For example, some protease inhibitors (PIs) can be taken either twice or once a day, boosted with a small dose of ritonavir. Shifting from a PI requiring 100 milligrams (mg) of ritonavir twice a day to a PI that only needs 100 mg once a day might also relieve diarrhea. If someone is taking a PI that is boosted with 200 mg of ritonavir once a day, they may benefit by changing the ritonavir dose to 100 mg twice a day. However, this should only be done under the guidance of your doctor.

Drug companies have also changed the formulation of some drugs to reduce the risk of diarrhea and other side effects. If drug-related diarrhea is severe or intolerable, it may be necessary to switch to a different drug. For instance, people with diarrhea related to nelfinavir or lopinavir may benefit by shifting to a drug like the PI atazanavir (Reyataz), which has a very low risk of diarrhea.

Question: Are there any practical measures people can take to relieve diarrhea?
CC: Some people benefit by eating foods containing soluble fiber, which absorbs water from the intestines and increases the bulk of stools. Foods like applesauce, bananas, oatmeal, white rice, and soft breads are rich in soluble fiber. It's important to know that foods containing another type of fiber -- insoluble fiber -- can actually make diarrhea worse. Foods high in insoluble fiber include the skin of fruits and vegetables, lettuce, whole-grain wheat and rice, and bran cereals.

Certain nutritional supplements may also be helpful. These include so-called probiotics, which contain a blend of "good" bacteria, such as Acidophilus. When good bacteria have been killed by antibiotics, probiotic supplements may help to restore them in the gut. Some people benefit by taking the nutritional supplement glutamine for diarrhea.

A number of over-the-counter and prescription drugs are also available. Over-the-counter drugs for diarrhea include Imodium, Kaopectate, and Pepto-Bismol. Prescription medications include Lomotil, octreotide, and tincture of opium.

Question: Are any new drugs being tested for diarrhea?
CC: An experimental drug called crofelemer is now being studied. Crofelemer is an extract from a medicinal plant from South America. In early studies, crofelemer reduced the release of excess fluid into the gut. It also helped relieve abdominal pain. The Community Research Initiative is one site currently involved in the ADVENT study, a clinical trial of crofelemer in HIV-infected persons.

To join the study, a person must have chronic diarrhea and a CD4 T-cell count above 100. The study has two stages. In the first stage, researchers will compare three different doses of crofelemer taken twice a day to a placebo (a dummy pill). In the second stage, everyone will be given the real drug for 20 weeks. If crofelemer is found to be safe and effective, its manufacturer will likely take steps to make the drug more widely available.

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Eric Brus is the Director of HIV Health Promotion at the AIDS Action Committee.