Medically reviewed by the clinical team at Consultants in Gastroenterology
Everyone experiences diarrhea occasionally. A stomach bug, a meal that did not agree with you, or a round of antibiotics can cause short-lived diarrhea that typically resolves on its own within a day or two. However, when diarrhea lingers, keeps returning, or begins to affect your daily life, your body is sending a signal that deserves attention.
Digestive symptoms can feel embarrassing to talk about, and many of our patients wait far longer than they should before seeking help, simply because they are not sure whether their symptoms are “serious enough.”
If diarrhea has lasted more than a few weeks or if it is disrupting your routine, it is time to schedule an appointment. You do not need to manage this alone.
What Is Considered “Persistent” Diarrhea?
Acute diarrhea lasts a few days and usually clears up without treatment.
Persistent diarrhea is generally defined as loose or watery stools that continue for more than two to four weeks.
Chronic diarrhea refers to symptoms that last four weeks or longer, or that come and go over months.
Nocturnal diarrhea wakes you at night and is worth highlighting. The bowel naturally slows during sleep, so diarrhea that interrupts sleep almost always has an organic cause rather than a functional one. This symptom should not be dismissed.
The first three distinctions matter because the causes and appropriate evaluations differ. A brief bout of diarrhea after traveling is a different situation entirely from diarrhea that has been present, on and off, for three months.
8 Common Causes of Persistent Diarrhea
Persistent diarrhea has many possible causes, and identifying the right one requires a proper evaluation.
Here are 8 conditions we most commonly find in our patients.
- Irritable bowel syndrome (IBS) is one of the most frequent diagnoses we make. IBS is a functional condition, meaning the digestive tract looks normal but does not work normally. The diarrhea-predominant type, often called IBS-D, causes loose stools, urgency, and cramping, frequently triggered by stress, certain foods, or hormonal changes. IBS is not dangerous, but it can be significantly disruptive, and it responds well to targeted treatment.
- Inflammatory bowel disease (IBD), which includes Crohn’s disease and ulcerative colitis, causes inflammation in the digestive tract that can produce persistent diarrhea, often accompanied by blood in the stool, abdominal pain, fatigue, and unintentional weight loss. IBD is a serious condition that requires diagnosis and ongoing management, but with the right treatment plan, most patients live full, active lives.
- Celiac disease is an autoimmune condition triggered by gluten, a protein found in wheat, barley, and rye. When a person with celiac disease consumes gluten, the immune system attacks the lining of the small intestine, leading to diarrhea, bloating, and poor nutrient absorption. It is more common than many people realize, and it is frequently undiagnosed for years.
- Microscopic colitis is a condition we see often, particularly in women over 50 and in patients who take certain medications such as NSAIDs or proton pump inhibitors. The colon appears normal on a standard colonoscopy, but a biopsy of the tissue reveals inflammation. The hallmark symptom is frequent, watery, non-bloody diarrhea, sometimes producing up to ten or more bowel movements per day.
- Bile acid malabsorption occurs when bile acids, which are produced by the liver to help digest fats, are not properly reabsorbed in the small intestine. They then pass into the colon and trigger watery diarrhea. This condition is underdiagnosed and is often mistaken for IBS.
- Small intestinal bacterial overgrowth (SIBO) happens when bacteria that normally live in the large intestine grow in excessive numbers in the small intestine. This can cause diarrhea, bloating, gas, and abdominal discomfort. SIBO can be confirmed with a simple breath test.
- Food intolerances, including lactose intolerance and fructose malabsorption, are among the more straightforward causes of persistent diarrhea. These do not involve immune reactions or structural damage, but they can cause significant discomfort if left unaddressed.
- Infections and post-infectious diarrhea also warrant a mention. Some bacterial, viral, or parasitic infections can cause diarrhea that lingers long after the initial illness. A condition called post-infectious IBS can develop after a gastrointestinal infection, even when the original pathogen is no longer present.
Symptoms That Should Prompt a Call to Our Office
You should contact us for evaluation if you are experiencing any of the following:
- Diarrhea lasting more than two to four weeks
- Diarrhea that keeps returning after brief periods of improvement
- Loose stools accompanied by blood or visible mucus
- Significant abdominal pain or cramping alongside diarrhea
- Unintentional weight loss
- Fatigue that seems out of proportion to your other symptoms
- Diarrhea that wakes you from sleep
- A recent course of antibiotics followed by ongoing loose stools
- A family history of IBD, celiac disease, or colorectal cancer
When Is It a Medical Emergency?
Please seek immediate care if your diarrhea is accompanied by high fever, signs of dehydration such as extreme thirst, dark urine, or dizziness, or if you are passing significant amounts of blood. Severe dehydration from diarrhea can develop quickly, particularly in older adults and young children, and it requires prompt treatment.
What We Will Look For
When you come in for an evaluation, we will take a thorough history of your symptoms, diet, medications, travel, and family background. From there, we may recommend blood work, stool studies, imaging, or endoscopic procedures, depending on your symptoms.
In many cases, a colonoscopy with biopsies is an important part of the workup, particularly if we are concerned about IBD or microscopic colitis. A colonoscopy not only allows us to examine the lining of the colon visually, but the biopsy samples also give us information that visual inspection alone cannot provide.
Our goal is not simply to stop diarrhea. Our goal is to find out why it is happening and treat the underlying cause.
A Word About Waiting
Patients often tell us they hesitated to come in because they were embarrassed or assumed the problem would go away on its own. We hear this regularly, and we want to address it directly.
Digestive symptoms are nothing to be embarrassed about. They are medical symptoms, no different from chest pain or a persistent cough. While some cases of diarrhea do resolve with time, persistent symptoms rarely improve without identifying and addressing their cause. Waiting longer does not make the evaluation easier. In some cases, it allows a treatable condition to progress unnecessarily.
You deserve an answer, and we are here to help you find one.
Reach Out to Consultants in Gastroenterology in Columbia, SC
If you have been dealing with persistent diarrhea, do not continue to manage it on your own. Our doctors at both Columbia, SC, locations are ready to listen, evaluate, and build a care plan tailored to your needs. We see patients at every stage, from those experiencing new symptoms to those who have been struggling for years without a clear diagnosis.
Your quality of life matters. Reach out to us today, and let us help you get back to feeling like yourself.
To schedule an appointment with one of our gastroenterologists, call our office or request a visit online. We look forward to taking good care of you.