Diabetes mellitus is a condition in which the body struggles to regulate blood sugar levels. It can create unique circumstances for diarrhea symptoms.
A person with both diabetes and diarrhea might have special considerations to bear in mind, for example when seeking medication for their condition.
Different complications of diabetes can cause or worsen diarrhea as well as the side effects of certain diabetes medications. The symptom occurs in up to 20 percent of people with diarrhea, according to studies in a 2016 journal article.
This article explores the link between diabetes and diarrhea and how to manage both.
Diabetes and diarrhea

Diabetic diarrhea is often highly persistent and debilitating.
Diabetes and some of its complications can lead to persistent diarrhea and affect the entire gut, from the mouth to the anus.
Diabetic diarrhea is different than other forms of diarrhea. This extremely persistent diarrhea can occur during the day or night and have a debilitating effect on everyday life and social interaction for people with diabetes.
On-going diarrhea occurs due to a range of diabetes symptoms that affect digestive function.
Autonomic neuropathy, the numbing effects of diabetes on automatic bodily processes in the nervous system, can impact on the consistency and frequency of bowel movements.
Diabetes is a major cause of autonomic neuropathy, and people with long-term diabetes complications in the nervous system also commonly experience effects in their GI system.
The stomachs of people with diabetes also experience delayed emptying of fluids and other foods, which can stagnate and cause bacterial overgrowth in the small intestine. This can also contribute to diarrhea symptoms.
Exocrine pancreatic insufficiency (EPI) can also occur in people who have diabetes. This is a condition in which the pancreas does not produce enough digestive enzymes. This deficiency, in turn, interferes with digestion.
A 2011 study showed that, on average, EPI occurs in 51 percent of people with insulin-dependent diabetes mellitus (IDDM, type 1) and 32 percent of people with non-insulin-dependent diabetes mellitus (NIDDM, type 2).
Between 4 and 9 percent of people with type 1 diabetes also have celiac disease, which can lead to uncomfortable and ongoing GI symptoms, including diarrhea.
People with diabetes should check for this condition with a doctor if long-term diarrhea has become a health issue.
Side effects of diabetes medication
Various long-term treatments for diabetes might also lead to severe and on-going diarrhea.
People use metformin, a medication, to treat type 2 diabetes. It is an effective drug for the condition, but up to 10 percent of people who take metformin experience side effects in the gastrointestinal (GI) system. One of these side effects is diarrhea.
The GI side effects of metformin may resolve with time. Some people, however, might need to stop taking the medication if diarrhea does not resolve.
Other diabetes medications that can have a similar effect include GLP-1 receptor agonists and DPP-4 inhibitors, as well as statins.
Treatments for diarrhea
Treatment for diarrhea depends on the cause.
If bacterial overgrowth is behind a presentation of diabetic diarrhea, treatment involves reducing the number of bacteria in the body and allowing healing time.
Controlling high blood glucose levels by treating diabetes is the first step toward preventing severe symptoms and complications, including diarrhea.
Some standard remedies and treatment can help any person with diarrhea, regardless of the cause.
The first step in treating any form of diarrhea is to drink water. Patients need to replace the lost fluids so that they do not become dehydrated. People with severe cases of diarrhea may need to be given fluid directly into their vein.
Other treatments include:
- Oral rehydration solutions: The World Health Organization (WHO) report a 90 percent success rate for their standard salt and glucose solution that helps treat dehydration in people with non-severe diarrhea.
- Over-the-counter (OTC) medication: Imodium or Pepto-Bismol are examples of medicines that may help to reduce stool liquidity and can be taken as soon as the first loose stool.
- Antibiotics: If bacterial overgrowth is causing diarrhea, an individual might need prescription medications to combat bacteria.
- Probiotics: Some food containing "good" bacteria, such as lactobacilli, have demonstrated helpful effects on diarrhea, reducing recovery time for 21 in every 100 people in this 2016 study.
- Dietary changes: High-potassium foods and drinks, such as diluted fruit juices free from added sugar, potatoes, and bananas. Salty dietary options, such as broth, salted crackers, and sports drinks, can also be useful.
Diet
Avoid the following foods to prevent the escalation of diarrhea symptoms:
- fried and greasy foods
- gassy foods, such as broccoli, beans, and prunes
- sugar alcohols, which are used as substitutes for sugar in some products
- milk, if intolerant to lactose
- caffeine
- alcohol
- carbonated sodas
Diagnosis
The focus in diagnosing diabetic diarrhea is separating it from other types of diarrhea that might stem from different causes.
Diabetic diarrhea commonly:
- occurs in intermittent periods
- might alternate with regular bowel movements
- occurs during the day and night
- is painless
Diabetic diarrhea is difficult to diagnose. It often does not present with uniform symptoms, often has a range of causes that work together, and sometimes resembles other types of diarrhea.
While every person experiences different bowel movements, there are some symptoms that may indicate when a medical problem is present.
The following symptoms might accompany diarrhea by:
- a loss of appetite
- bloating
- nausea
- vomiting
- difficulty swallowing
- heartburn
If these symptoms become apparent, discuss them with a physician, especially since they can lead to dehydration.
Monitor the following characteristics of stools ahead of a visit to a doctor when passing stools, such as:
- when the diarrhea started
- any medication that may have altered the stool
- the frequency and consistency of bowel movements
- if blood is present in the stool
- if nausea and vomiting also occur
When it comes to testing for and treating diarrhea, all the above conditions can contribute. People should keep a food diary to monitor for potential triggers. A person could end up having another GI tract problem due to celiac disease or lactose intolerance.
The doctor will often use both laboratory testing and a full clinical assessment to isolate the cause of diarrhea symptoms, especially when they relate to underlying diabetes complications.
Prevention

Managing diabates can help control its symptoms, but preventing diabetic diarrhea specifically can be difficult.
People with diabetes might find it difficult to prevent diarrhea, as complications such as autonomic neuropathy require wide-ranging, on-going management.
However, the following steps might reduce the risk or impact of diarrhea symptoms:
- Drink clean water: Purchase bottled water when unsure of local water sources or hygiene.
- Wash the hands with soap and warm water: Always do so after touching public places, using the toilet, and helping a child use the toilet, as well as before and after preparing food.
- Hand rub: Use an antibacterial hand rub when soap and water is unavailable. This can reduce the risk of diarrhea from bacterial causes.
People with long-term diarrhea should track their symptoms and discuss them with a doctor to determine and treat the underlying cause.
Q:
What are the main differences between diabetic diarrhea and other types?
A:
Other types of diarrhea may be more easily treatable and temporary than diabetic diarrhea.
For example, if diarrhea occurs due to acute gastroenteritis, a viral infection, your body tends to resolve the diarrhea without active treatment. Viral gastroenteritis may cause abdominal pain, nausea, vomiting, and fever.
If a person has celiac disease or lactose intolerance, dietary changes usually help to keep diarrhea and associated symptoms at bay, such as abdominal bloating. Uncontrolled diabetes mellitus, however, could cause chronic problems in the GI tract, possibly with recurring episodes of diarrhea.
Diarrhea related to diabetes is typically a progressive process once it sets in.
Additionally, diabetic diarrhea may be painless. The evaluation and treatment for diabetic diarrhea may not be as simple as diagnosing other causes of diarrhea. If you find yourself with episodes of diarrhea that do not resolve over time, a physician can help you figure out the cause and find the appropriate treatment.
If you have diabetic diarrhea, the treatment approach will likely have multiple factors and will include trying to control your blood glucose levels.
Stacy Sampson, DO Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.