Diarrhea — loose or watery stool (poop) — is a common problem that most people experience a few times a year. If you’re living with a kidney disease like IgA nephropathy, C3 glomerulopathy, or others, you may have to take extra precautions if you have diarrhea.

Continue reading to find out what you should know about diarrhea if you’re living with kidney disease.

1. Diarrhea Can Make Kidney Disease Worse

Severe diarrhea can lead to complications that can worsen kidney disease or cause kidney failure. In severe cases, diarrhea can cause you to become dehydrated and disrupt the balance of electrolytes (essential minerals) in your body. Dehydration can decrease blood flow to your kidneys and cause sudden or acute kidney injury (AKI), also called acute renal failure or kidney failure. A study found that 1 out of 10 adults hospitalized for diarrhea develop AKI. If you have AKI, your kidneys aren’t able to filter waste products from your blood, which then build up in your blood, causing serious problems.

The signs and symptoms of acute kidney injury include:

• Not enough urine leaving your body
• Fatigue
• Edema (swelling from fluid buildup) in your lower legs, feet, ankles, and/or around the eyes
• Confusion
• Chest pain
• Shortness of breath

AKI can lead to permanent kidney damage, which may worsen kidney disease. People with chronic kidney disease (CKD) and hypertension (high blood pressure) may be more susceptible to developing AKI when they have diarrhea.

Although it’s possible to get AKI from any kind of diarrhea, it’s most likely when you have diarrhea caused by an infection.

2. People With Kidney Disease May Have an Increased Risk of Diarrhea

Kidney disease can affect different parts of your body, including your digestive tract.

Even though constipation (not passing stools regularly) is usually the most common digestive problem associated with kidney disease, diarrhea is also common for many people with kidney disease.

A recent study published in BMC Nephrology showed that people with the kidney disease IgA nephropathy experienced higher rates of diarrhea than people without the disease, especially those who were female. There are several reasons people with kidney disease may have an increased risk of developing diarrhea.

Weakened Immune System

People with kidney disease can have a weakened immune system that makes them more likely to develop an infection. The higher risk of infection is due to a number of factors, including:

• Older age — More than half of people over 75 years old have kidney disease.
• Immunosuppressive therapy — You may take drugs that weaken your immune system to treat some kidney diseases or to prevent a kidney transplant rejection.
• Other medical conditions — Conditions such as diabetes or autoimmune conditions can increase infection risk.
• Dialysis — This procedure itself can also increase your risk of infection.
• Malnutrition — People with kidney disease have a higher risk of being malnourished, which increases the risk of infection.

CKD is also one of the main risk factors for developing an infection that causes severe diarrhea, called Clostridioides difficile infection (CDI). CDI, often called “C. diff,” is caused by bacteria that can infect the large intestine. Symptoms of CDI can range in severity from diarrhea to life-threatening intestinal damage. CDI is most common in people who have recently taken an antibiotic or stayed in a health care facility, like a hospital.

Antibiotic Use

If you have a weakened immune system due to kidney disease, you may also be more likely to need antibiotics to help fight off a bacterial infection. Many antibiotics can cause diarrhea because they disrupt the balance of good and bad bacteria in your gut.

Some antibiotics are more likely to cause diarrhea than others. The antibiotics that are most commonly associated with diarrhea include:

• Amoxicillin (Amoxil, Moxtag)
• Cefdinir
• Cephalexin (Keflex)
• Ciprofloxacin (Cipro)
• Clarithromycin (Biaxin)
• Levofloxacin

You may be more likely to get diarrhea from antibiotics if you’re taking them for a longer period of time or taking more than one at a time. Talk to your doctor about the risk of diarrhea from any new antibiotic you’re taking.

Other Medications

Medications other than antibiotics can also cause diarrhea, including:

• Heartburn medications, such as antacids with magnesium
• Proton pump inhibitors (PPIs) for heartburn, such as omeprazole (Prilosec), esomeprazole (Nexium), and pantoprazole (Protonix)
• Immunosuppressant medications, such as mycophenolate (CellCept, Myfortic)
• Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Motrin) and naproxen (Aleve)
• Diabetes medications, such as metformin (Glucophage, Fortamet)
• Antidepressants, such as sertraline (Zoloft), fluoxetine (Prozac), and escitalopram (Lexapro)
• Chemotherapy drugs

People with CKD may be more likely to take some of these medications, like PPIs, that can cause diarrhea and increase the risk of CDI.

You might take mycophenolate if you’ve had a kidney transplant or to treat kidney disease caused by an autoimmune condition, such as lupus.

You may take an antidepressant if you also have depression, which is more common in people with kidney disease than in the general population.

Although about one-third of adults with diabetes also have CKD, people with kidney disease usually don’t take the diabetes medication metformin. Talk to your doctor to find out if other medications used to control your blood sugar may cause diarrhea.

Talk to your nephrologist about the possible side effects, like diarrhea, of the medications you take and how they may affect your kidneys.

3. You May Need To Avoid Certain Diarrhea Treatments With Kidney Disease

If you have diarrhea, you may want to reach for an over-the-counter (OTC) or at-home remedy. However, some of these treatment options can be dangerous for people with kidney disease. This is especially true for medications that contain electrolytes.

Check with your nephrologist or dietitian before using any at-home treatments for diarrhea.

Magnesium Hydroxide

Magnesium hydroxide (milk of magnesia) is an example of a medication that you should be wary of if you have kidney disease. This OTC medication can be used to treat upset stomach, heartburn, and constipation. You may be tempted to take this medication if you have diarrhea and an upset stomach. However, magnesium can disrupt your electrolyte balance and cause kidney damage.

Rehydration Therapy

Recommended home remedies to treat diarrhea often include rehydration therapy with fluids containing electrolytes and glucose (sugar), such as:

• Broth
• Soft drinks without caffeine
• Fruit juice
• Sports drinks (like Gatorade)

However, if you have kidney disease, you may have restrictions on how much fluid, sodium, and potassium you can have each day. It’s important to check with your nephrologist or dietitian before adding these to your diet.

Diet

When you have diarrhea, it’s generally better to stay away from greasy or fatty foods and stick with foods that are easier to digest. Health care providers sometimes recommend the BRAT diet, with “BRAT” standing for “bananas, rice, applesauce, toast.”

However, if you have kidney disease, you may need to avoid bananas, which are rich in potassium. You should also be mindful of the salt and electrolyte content of any rehydration therapy you use.

Talk to your doctor about the best foods to eat when you have diarrhea, especially if you are on a renal diet.

4. Diarrhea Can Have Various Potential Causes, So Being Careful Is Important

If you’re living with kidney disease, it’s important to take steps to prevent diarrhea. Although the cause of diarrhea is often unknown, you should be aware of the most common causes of diarrhea, such as:

• Bacterial infections
• Foods that upset your digestive tract
• Food allergies or intolerances
• Trouble absorbing food
• Laxatives

Other things you can do to prevent diarrhea include:

• Washing your hands often with soap and water
• Washing fresh fruits and vegetables before eating them
• Storing food properly
• Being cautious about drinking tap water when you travel

What Should You Do if You Have Diarrhea?

If you have diarrhea, it’s important to talk to your doctor or nephrologist about the best treatment options for you. Contact your doctor right away if you have symptoms of serious diarrhea, such as:

• Fever
• Vomiting
• Weakness
• Weight loss
• Blood in your stool

Talk With Others Who Understand

On MyKidneyDiseaseCenter, the site for people with kidney disease and their loved ones, people come together to gain a new understanding of different types of kidney disease and share their stories with others who understand life with kidney disease.

How have you managed diarrhea with kidney disease? Post your experience in the comments.