20 Warning Signs You May Have a Kidney Problem

From back pain to bloody noses, these are the symptoms of serious kidney conditions.


The kidneys are among the most important organs in your body, responsible for filtering waste, producing red blood cells, and even keeping your bones strong and sturdy. But despite the many vital roles they play in maintaining a healthy, high-functioning body, it can be hard to determine when these bean-shaped organs aren't operating at full capacity—especially in the early stages of certain kidney problems. In fact, according to Cynthia Smith, a nurse practitioner with Renal Consultants, approximately "one in three Americans are at risk of developing chronic kidney disease (CKD)" and "fewer than 50 percent of those with severe CKD know they have a problem." With that in mind, we've compiled the 20 most common—and debilitating—signs you may have a kidney problem. If you experience any of these symptoms, consult your doctor immediately to address the issue.

Back pain

couple with back pain, signs you need a new mattress

One of the first noticeable signs you might have a kidney issue is having back pain. Since your kidneys are actually higher up in your abdomen underneath your ribcage, a kidney infection can cause intense pain in the middle to upper back area, according to the Cleveland Clinic. Depending on the severity of the infection, this pain can also spread to the abdomen and groin.

Side pain

Woman at the office with a pain in her side

Kidney stones, which are hard deposits of salt and minerals that form inside the kidney, can be extremely painful when they pass through the ureter and bladder. In fact, according to Los Angeles-based urologist S. Adam Ramin, MD, the pain is often "compared to [that] of childbirth." The Mayo Clinic says that you'll know the pain you're experiencing is from kidney stones when it's in your side and back and comes in waves, not unlike a kidney infection.


Man feeling nauseous with stomach pain

When a kidney stone moves from your kidney to your ureter, it can block the passing of urine. When this happens, Ramin says you may experience "swelling and pain, which can be accompanied by nausea and vomiting."

Frequent urination

Unrecognizable woman, sitting on a toilet and rewind and tear off a toilet paper. Concept image of digestive problems and difficulties in the toilet.

If you find yourself heading to the restroom with increased frequency, it could be a sign that something is up with your kidneys. "If the kidney filters are damaged, it can cause an urge to urinate, especially at night," says Renee Matthews, MD. Considering that frequent urination is also associated with health issues like diabetes and urinary tract infections, this symptom definitely merits a trip to the doctor.

Foamy urine

White hand flushing a toilet in the bathroom

Often when kidney function is impaired, "[the] urine has bubbles that won't go away when you flush the toilet," says Matthews. "This foam is similar to the foam you see when scrambling eggs because the protein found in urine is albumin, which is the same protein that is found in eggs."

Blood in your urine

Close-up of steel toilet handle

According to Matthews, this is another common symptom of kidney disease. If you notice blood in your urine or you notice it looks even a little bit red or brown, it's important that you get to a doctor before any potential problems get worse.


Bathroom door open looking at a toilet

Though kidney problems often affect your body's urinary tract, they can sometimes cause problems with your bowels, as well. According to oncologist Przemyslaw Twardowski, MD, kidney cancer can cause "disturbances in body chemistry"—namely, an overabundance of calcium in the bloodstream—that can lead to constipation. If you're experiencing this issue and think it's a sign of a bigger problem, talk to your primary care provider about having your calcium levels checked.


Woman rubbing her temples with headache and dizziness

According to the National Institute of Diabetes and Digestive and Kidney Diseases, patients with kidney failure often develop anemia due to a decreased production of erythropoietin (EPO), a hormone that typically triggers the production of red blood cells. And a very common symptom of anemia is feeling lightheaded or dizzy—others include weakness, headaches, paleness, and difficulty breathing.


Wife Comforting Senior Husband Suffering With Dementia and looking confused

If your brain is feeling a bit fuzzy, and you're just not at your sharpest mentally, this could be a sign of a kidney problem. According to a 2012 study from Temple University, decreased kidney function is strongly correlated with cognitive impairment and verbal memory issues. And, according to Twardowski, high calcium levels caused by kidney cancer can result in feelings of confusion.

Chronic itching

Close-up Of An African Man Scratching His arm

Excessive urea in the bloodstream caused by kidney malfunction can cause serious itching—a symptom not to be taken lightly. In fact, a 2015 paper published in Seminars in Nephrology notes that up to 40 percent of patients with end-stage kidney disease develop pruritus, or chronic itching.

Swollen hands and feet

Woman with swollen ankle foot

Since the kidneys are responsible for filtering excess water from the body, when they aren't performing this function properly, the excess water builds up and causes swelling in the hands, feet, and ankles, according to the National Kidney Foundation. The organization notes that this can also be a symptom of heart failure—so either way, it's not something that should be ignored.

Swelling around your eyes

Woman with swelling around the eyes

According to the Mayo Clinic, kidney disease can create "extra fluid and sodium in your circulation," which leads to swelling in different areas of the body—often around the eyes when the issue is kidney-related. In the case of nephrotic syndrome, in which too much protein is secreted through the urine, swelling also occurs due to lower levels of albumin in the blood.

Bad breath

Shot of a handsome young man smelling his breath during his morning grooming routine

When your kidneys aren't on top of their filtering duties, waste products often show up in unexpected places. In fact, Jennifer Schau, DDS, notes on her website that when your kidneys are unable to filter out the excess urea in your bloodstream, you may notice a "foul odor" being emitted from your mouth—in other words, you have bad breath.

Gum disease

Woman getting her teeth looked at at the dentist's office

Bad breath isn't the only way in which kidney disease can manifest in your mouth. According to Schau, kidney issues can also cause gum disease, "leading to the decay and loss of teeth." A 2013 meta-analysis published in the Pakistan Journal of Medical Sciences found that patients with chronic kidney disease are far more likely to have periodontal disease, as well as other issues like overgrown gums and dry mouth, than those without serious kidney problems.

Loss of appetite

Man is not eating lies over 40

If your favorite foods suddenly seem less appetizing, you might be dealing with a kidney issue. According to the National Kidney Foundation, "a buildup of toxins resulting from reduced kidney function" can result in a decreased appetite.

Inability to eat meat and dairy

Man eating a carrot and saying no to a piece of steak

Interestingly enough, advanced kidney disease can make protein-rich foods like meat and dairy taste absolutely terrible. According to the Kidney & Urology Foundation of America, that's because these foods break down into nitrogen and creatinine, waste products that unhealthy kidneys are unable to filter out of the bloodstream.

Shortness of breath

man short of breath

When your kidneys aren't properly filtering and excreting waste products and fluid, the Urology Care Foundation notes that shortness of breath can occur, particularly if fluid has built up in your lungs.

High blood sugar

Man with Diabetes Testing His Blood Sugar Misdiagnosed Men's Health Issues

According to the National Kidney Foundation, diabetes is the leading cause of kidney failure, accounting for 44 percent of new cases. Due to the toll diabetes takes on the kidneys as a result of the damage it does to the body's red blood cells, diabetics are also at risk of developing diabetic kidney disease, a condition that further reduces kidney function.

Chronic nosebleeds


Granulomatosis with polyangiitis (GPA) is a disease characterized by swelling of the blood vessels in the kidneys, nose, sinuses, throat, or lungs. According to the American Kidney Fund, the first sign of this condition is usually a runny nose or frequent nosebleeds. Though GPA doesn't always affect the kidneys, any case that does can lead to chronic kidney disease or even kidney failure, so it's important to speak to a doctor if nosebleeds become a regular occurrence.

Unintentional weight loss

Black woman stepping on a scale to weigh herself

Weight loss isn't always a good thing, especially if it's unintentional. If you're shedding pounds for no reason, it may be because your kidneys aren't functioning properly. After monitoring 3,933 patients with CKD for nearly six years, the researchers behind a 2018 study published in the Official Journal of the National Kidney Foundation found that "significant weight loss [begins] relatively early during the course of CKD."

Additional reporting by Sarah Crow.

Filed Under
Best Life
Live smarter, look better,​ and live your life to the absolute fullest.
Get Our Newsletter Every Day!
Enter your email address to get the best tips and advice.
close modal
close modal