When Diarrhea Needs Medical Attention

As the Centers for Disease Control (CDC) investigates a multistate cyclosporiasis outbreak, people have questions about diarrhea that can be uncomfortable or are embarrassed to ask: when is diarrhea just an inconvenience and when is it a symptom to treat? 

For Milwaukee residents, news headlines and conversations about cyclosporiasis may bring back memories of the city's 1993 cryptosporidium outbreak. A parasite in the public water supply sickened an estimated 400,000 people. Although both cyclospora and cryptosporidium are microscopic parasites that can cause watery diarrhea, they are different organisms, they spread through different types of exposures, and they are detected with different tests. Diarrhea can be a symptom of many different illnesses, and getting the correct diagnosis will ensure you treat it safely and correctly. 

When to Seek Care for Diarrhea 

What one person considers to be diarrhea may not be the same for the next. Clinicians use the Bristol Stool Chart as a guide to describe stool consistency, shape and texture. The chart helps a doctor categorize the stool into seven types and determine if it is objectively constipation, healthy or diarrhea. Generally, diarrhea means having stools that are loose or more watery than normal, often with more frequent bowel movements. A good rule-of-thumb is to go to the doctor if loose stool persists for more than two days or if you see blood in the stool. 

"Anyone can have a day of loose stool, but if it is lasting into two days or more, or if it contains blood, this can signal an infection or other condition that needs medical attention,” said Mary Beth Graham, MD, infectious disease specialist and MCW faculty member. “Your doctor will ask you questions to determine next steps and will need a sample of the stool to figure out what is causing the symptoms. For example, if diarrhea is infectious in nature, blood in the stool is usually associated with a bacterial infection or possibly some viral infections, but not usually with parasitic infections.” 

Talk to your doctor if you have new onset diarrhea or a change in your usual bowel pattern and: 

• the diarrhea lasts two days or longer 
• there is blood in the stool 
• you have a fever, significant abdominal pain or worsening cramping 
• symptoms improve and then return you recently took antibiotics 
• you recently traveled, camped, drank untreated water or may have eaten food connected to an outbreak 
• you have signs of dehydration, such as dry mouth, dizziness when standing, unusually dark urine or urinating less often 
• you are pregnant, an older adult, immunocompromised or have another condition that increases the risk of severe illness 

A primary care team or urgent care team can evaluate symptoms and order stool testing. For mild to moderate symptoms, a virtual care visit may also be a convenient first step to discuss symptoms and determine whether stool testing or an in-person evaluation is needed. 

Diarrhea rarely requires a visit to the emergency department. Going to the emergency department does not speed up testing or treatment. Emergency care is appropriate, however, for severe dehydration, fainting or confusion, inability to keep liquids down, severe abdominal pain or a large amount of blood in the stool. 

Stool Testing For Accurate Diagnosis and Treatment of Diarrhea 

Diarrhea can be caused by a number of different organisms, including bacteria, viruses or parasites. For example, norovirus is one of the most common causes of acute gastroenteritis outbreaks in the United States and in Wisconsin. Campylobacter causes more bacterial diarrheal illnesses than any other bacterium in the country, and giardia is the most common intestinal parasitic infection. Other frequent or clinically important causes include salmonella, shigella, Clostridioides difficile or C. diff, cryptosporidium and cyclospora. The symptoms often overlap, presentations vary from patient to patient and most importantly, the treatment can be very different. This is why a stool test is important to determine how to treat diarrhea. 

"It is such a broad spectrum of illnesses,” Dr. Graham said. “They can all look the same, and you cannot know how to treat until the appropriate test is done. I just saw a patient who I was convinced had cyclospora, and she actually came back positive for salmonella. She had gone to urgent care, and they did a stool culture and a C. diff test. I had her submit a new sample to test for cyclospora, but several days later the culture came back positive for salmonella.” 

There is no single diarrhea test because each organism requires its own. There are also many different types of tests, such as stool cultures, molecular or PCR tests, antigen tests and parasite-specific tests. One stool sample may be used for several tests, but the lab will only run the tests the clinician requests, which is why the conversation with the clinician to gather a history and assess symptoms is important. 

Common diarrhea-related illnesses to test for and treat include:

Stool testing also improves what public health officials know about an outbreak. Many infections are never formally diagnosed because the person does not seek care or submit a stool sample. Confirmed cases help investigators find patterns, identify a possible source and reduce illnesses. 

Should You “Ride it Out” or Treat the Diarrhea? 

For many diarrhea-related illnesses, the treatment is supportive care and time. Many otherwise healthy people recover from infectious diarrhea with fluids and rest. However, testing is helpful because the correct treatment plan is based on which organism is causing diarrhea, and that treatment can vary person-to-person. Even though the symptoms are similar, some infections require antibiotics, some can be worsened with over-the-counter medications and some may need follow-up care. 

"Some illnesses, like salmonella, you actually don't treat, because it can prolong a carrier state of the bacteria, meaning the person can pass it on to others for an extended period of time," Dr. Graham said. "With cyclospora, if people can keep hydrated and are not dizzy, the treatment is to ride it out at home with hydration and no antibiotics. For others, antibiotics may be necessary. None of the treatments are the same, and that's why the test matters even when the answer could be rest." 

The Problem With Over-the-Counter Anti-Diarrheal Medications 

When you have diarrhea, it can be tempting to immediately take loperamide, sold as Imodium, or other medications that slow the bowel. However, this is not appropriate for every infection and could make things worse. 

“Slowing the bowel may keep an organism or its toxins in the intestines longer,” Dr. Graham said. “Using anti-diarrheal medications can be particularly concerning when there is bloody stool, fever, suspected C. diff or another inflammatory infection. I always urge people who want to self-treat their diarrhea to wait until they know what is causing it.” 

Over-the-counter medications can also mask the severity of the illness, which could further delay testing. 

When you have diarrhea, the most important thing you can do is to stay hydrated. Loose stool removes both fluid and electrolytes from the body. Drinking plain water is helpful, but water alone may not replace what has been lost. You can alternate water with sports drinks that are designed to replenish electrolytes or Pedialyte, if you want an option with less sugar. Probiotics, a bland diet and soluble fiber may also help. If diarrhea persists for two days or more or there is blood in the stool, talk to your doctor or go to urgent care.

Learn More About Care Options