A stinging sensation when you pee, cramping in your lower belly, an intense urge to tinkle all day long. Anyone who’s ever had a urinary tract infection (UTI) knows it’s not pleasant. Add on gut health issues like diarrhea, and you might be wondering what’s up. Is an upset stomach usually a UTI symptom?

While it’s rare, it’s possible to have UTI-induced diarrhea. Whether this comes from the infection itself, UTI treatments like antibiotics, or something else entirely, will likely depend on the person.

Here, a urologist answers all your burning questions, plus offers tips on treating UTI and diarrhea at the same time (and how to prevent UTIs in the first place).

Can a UTI cause diarrhea?

“In general, local urinary tract infections do not cause diarrhea,” says Marisa M. Clifton, MD, FACS, director of women’s health in the Brady Urological Institute at Johns Hopkins Medicine. But it’s not impossible.

The bladder and bowel are both affected by the same network of nerves. “The nerves that innervate (or stimulate) the urinary tract also innervate the bowel,” says Dr. Clifton. That means what happens in one area can potentially affect the other. For example, if you’re constipated, you might have more bladder symptoms, and vice versa.

“When patients have significant infections that have gone beyond the urinary tract, they can have gastrointestinal symptoms,” says Dr. Clifton. But this is pretty rare, she adds.

Other symptoms of a UTI

While diarrhea isn’t a common UTI symptom, there are some telltale signs of this kind of infection. These include the following, per Penn Medicine:

• Cloudy or bloody urine, which may have a foul or strong odor
• Low-grade fever in some people
• Pain or burning with urination
• Pressure or cramping in the lower abdomen or back
• Strong need to urinate often, even right after the bladder has been emptied

If left untreated, you can develop bladder infection complications, including the infection spreading to your kidneys. Kidney infections can cause gastrointestinal issues like nausea and vomiting, as well as the following symptoms, per Penn Medicine:

• Chills, shaking, or night sweats
• Fatigue and a general ill feeling
• Fever above 101°F (or 38.3°C)
• Pain in your side, back, or groin
• Flushed, warm, or reddened skin
• Mental changes or confusion (this symptom is often the first or only sign of a UTI in older adults)
• Occasionally, severe abdominal pain

Though rarer, UTIs can also cause other serious complications such as kidney damage or scarring and sepsis (a potentially life-threatening blood infection), according to Penn Medicine. In healthy adults, “most lower urinary tract infections do not progress to significant bloodstream infections,” says Dr. Clifton. That said, the risk of sepsis is higher in certain groups, including infants, older adults, and people with compromised immune systems.

On the flip side, can diarrhea cause a UTI?

When you have the runs, odds are you’re spending more time wiping your bottom. But the way you wipe could, in theory, increase your UTI risk. If you wipe from back to front (instead of the more hygienic way—front to back), you can unintentionally transfer bad bacteria like E. coli from your butt to your urethra, aka your pee hole, per the Cleveland Clinic.

People with vaginas are more susceptible to getting UTIs this way because their urethras are shorter and closer to the anus. Still, there’s not much research to support the idea that front-to-back wiping completely prevents urinary tract infections, says Dr. Clifton.

While your wiping technique may (or may not) increase your odds of a UTI, the products you use to clean your butt can definitely raise your UTI risk. When you’re dealing with diarrhea, you might feel the need to scrub your butt with heavy-duty soaps to ensure it gets squeaky clean. But “cleaning with harsh soaps (or douching) can change your genital flora, or the healthy bacteria that prevent overgrowth of bad, pathogenic bacteria,” says Dr. Clifton. “This can predispose you to UTIs and create irritation.”

“When patients have significant infections that have gone beyond the urinary tract, they can have gastrointestinal symptoms.” —Marisa Clifton, MD, urologist

Can UTI medications cause diarrhea?

They sure can. “Bacterial urinary tract infections are routinely treated with antibiotics,” says Dr. Clifton. And one of the most common antibiotics side effects is nausea and diarrhea.

Here’s why: Even though you take an antibiotic to kill harmful bacteria, the drugs can’t discriminate between the good and bad bugs in your gut. In other words, antibiotics wipe out everything—including the healthy flora in your GI tract that your body needs to digest food, says Dr. Clifton.

Without this armor of good bacteria, your body can be left vulnerable against harmful infections. For example, taking antibiotics can lead to an overgrowth of bad bacteria like C. difficile (or C. diff), says Dr. Clifton. Matter of fact, you’re up to 10 times more likely to get C. diff during a course of antibiotics (and the month after), according to the Centers for Disease Control and Prevention (CDC).

C. diff from UTI treatments like antibiotics can cause the following symptoms, per Dr. Clifton:

• Diarrhea
• Sweating and chills (and sometimes, poop sweats)
• Stomach pain
• Nausea
• Colitis—an inflammation of the colon

In severe cases, C. diff infections can also result in extensive colon damage or even death, per the CDC. If you feel these symptoms while taking antibiotics (or shortly thereafter), it’s important to call your doctor and get care as soon as possible.

On top of digestive symptoms, antibiotics can also cause other unpleasant side effects like rash, dizziness, and yeast infections, according to the CDC. Given all the potential side effects, “it’s very important to be thoughtful about using antibiotics, and to have thorough conversations with your care team about how you’re feeling,” adds Dr. Clifton.

How to treat UTI-related diarrhea

A combination of lifestyle changes and over-the-counter (OTC) supplements could help treat your digestive distress.

Ask about switching to another antibiotic

If the antibiotic you’re taking to treat a UTI causes diarrhea, let your doctor know. They may be able to prescribe a different antibiotic, or recommend another way to ease digestive issues while still treating your UTI, says Dr. Clifton.

Take a probiotic

You might also “consider taking a probiotic at the time of antibiotic treatment, to counteract its negative effect on the healthy bacteria,” adds Dr. Clifton. By taking probiotic supplements or eating probiotic-rich food (which have good bacteria and yeasts), you can repopulate your gut with healthy microbes and possibly regulate your bowels.

Stay hydrated

For both UTI and diarrhea treatment, it’s important to drink plenty of water. Drinking enough water can help you pee more often and flush out the bacteria in your bladder causing the infection. And when you have diarrhea, you tend to lose a lot of fluid; drinking water or electrolyte-infused beverages like Pedialyte can help up your levels.

In addition, drink plenty of water. When you have diarrhea, you lose a lot of fluid, so it’s important to replenish it to stay hydrated.

Pay attention to your poop

Last but not least, monitor your poop. While your poop’s shape and color can change for a number of reasons, like diet changes or stress, “severe or foul-smelling diarrhea could be a sign of C. difficile,” says Dr. Clifton. Left unchecked, C. diff could become potentially life-threatening for some people such as older folks, per the CDC.

On top of diarrhea and nausea, other symptoms of C. diff to look out for include fever, stomach tenderness or pain, and loss of appetite, according to the CDC. If you experience any of these, call your doctor right away. C. diff infections won’t just go away on their own and require treatment with targeted antibiotics.

How to prevent a UTI that causes diarrhea

With a few tweaks to your daily routine, it’s possible to prevent UTIs (and subsequent antibiotic-related runs) from happening in the first place. Try these tried-and-true tips from the Cleveland Clinic:

• Practice good hygiene: Always wipe from front to back after a bowel movement and change your period products, including pads and tampons, frequently.
• Drink plenty of fluids: Sipping six to eight glasses of water daily can help flush out bacteria from your urinary tract.
• Don’t hold your pee for too long: Peeing frequently can help remove waste from your body and reduce your risk of developing an infection, especially if you get UTIs a lot. If you tend to hold your pee a little too long (say, when you’re busy at work), try setting up a bathroom schedule for yourself, to make sure you’re peeing (and pooping) regularly.
• Pee before and after sex: Sex can introduce bacteria to your urethra, so peeing before and after sex can help flush it out.
• Talk to your doctor about other birth control options: Some people have an increased risk of developing a UTI if they use a diaphragm for birth control.
• Use a water-based lubricant during sex: Other types of lube, including scented varieties and spermicide, can upset the balance of bacteria in your genital area.
• Wear breathable clothing: Loose-fitting clothing and cotton underwear can help prevent moisture from accumulating around your urethra, which often contributes to UTI and yeast infection formation.
• Ask your doctor about medications or supplements: OTC supplements—including cranberry extract and probiotics—may help prevent UTIs, as well as vaginal creams with estrogen if you’re postmenopausal.

When to see a doctor

It’s possible for some asymptomatic UTIs to resolve on their own (up to a third can be flushed out with hydration, according to Dr. Clifton). But UTIs with symptoms rarely go away on their own, and need to be treated with medication, per the Mayo Clinic.

Dr. Clifton says you should see your doctor ASAP if:

• Your symptoms remain persistent or worsen
• You have severe diarrhea that’s foul-smelling
• You can’t stay hydrated
• You have blood in your urine

Go to the ER immediately if you develop the following symptoms, which can be a sign that the infection spread to your kidneys, per the Cleveland Clinic:

• Fever
• Back pain
• Vomiting

Some people have an increased risk for recurrent or serious UTIs. “These patients may have a history of urinary tract surgery, nerve issues affecting their bladder function, or a compromised immune system,” says Dr. Clifton. If you fall into one of these groups, call your doctor as soon as you notice any symptoms of UTI, to keep things from getting worse.

FAQ

What are the signs of a complicated UTI?

Most UTIs are considered “simple.” This means, they happen in the lower urinary tract (bladder and urethra) in healthy, nonpregnant people with vaginas, says Dr. Clifton. The most common symptoms of a simple UTI are:

• Pain with peeing
• An urgent need to pee (and/or incontinence)
• Peeing more frequently

A complicated UTI, on the other hand, can pose a higher risk of complications. They happen in people who are pregnant, people with prostates, and people with compromised immune systems, says Dr. Clifton. They can also happen if you have a fever, kidney stones, sepsis, a catheter, or nerve issues affecting bladder function, she adds.

Complicated UTIs can also cause different symptoms than simple UTIs, says Dr. Clifton. You might have:

• Fever
• Chills
• Pain in the prostate area (if you’re a person with a prostate)
• Other pains or systemic symptoms

Because complicated UTIs are, well, more complicated to treat than simple UTIs, they often require a longer duration of treatment, different antibiotics, and sometimes, even hospitalization.

What causes a UTI?

UTIs happen when germs (typically bacteria) enter your urethra. From there, they may travel to your bladder, or even up to your kidneys.

The most common culprit of UTIs is a bacterial strain called E. coli, which lives in your large intestine and can be present in your poop. E. coli causes more than 90 percent of bladder infections, per the Cleveland Clinic, and it can be spread through things like sex, wiping back to front in the bathroom, or from touching contaminated surfaces.

UTIs can also happen if the balance of bacteria in your urinary tract gets out of whack. You can unknowingly upset your equilibrium by using certain products (think: harsh soaps and scented lubricants), douching, sporting underwear made with synthetic materials, and tight-fitted clothing, according to Planned Parenthood.

On top of this, certain conditions raise your risk for getting a UTI. These include the following, per Penn Medicine:

• Menopause
• Diabetes
• Conditions that affect personal-care habits (like Alzheimer’s disease or delirium)
• Problems emptying your bladder completely
• Having a urinary catheter
• Bowel incontinence
• Enlarged prostate, narrowed urethra, or anything that blocks the flow of urine
• Kidney stones
• Staying still (immobile) for a long period of time (for example, while you’re recovering from a hip fracture)
• Pregnancy
• Surgery or other procedures involving the urinary tract

—reviewed by Jennifer Logan, MD, MPH