What are bladder stones?

Bladder stones form when minerals in urine (pee) crystalize and clump together in the bladder. The medical term for bladder stones is bladder calculi.

Bladder stones generally develop when some urine stays in the bladder after you pee. Without treatment, stones can cause infections, bleeding and long-term problems in the urinary tract.

Who is likely to get bladder stones?

Anyone can get bladder stones, but men over 50 are more likely to develop them. Around half of men over 50 have a condition called benign prostatic hyperplasia (BPH). BPH causes the prostate (an organ located below the bladder in men) to get bigger. An enlarged prostate can make it difficult to drain the bladder. Stones can form when urine sits in the bladder for too long.

People who have nerve damage such as a spinal cord injury affecting the bladder are more likely to get bladder stones. Also, individuals who have had specific types of surgery on their bladder (such as enlargement of the bladder with intestine) are also at risk of bladder stones. Very rarely, a bladder stone will be the result of a kidney stone that could not pass out of the bladder. This can occur in people who have difficulty draining urine out of their bladder, such as men with BPH.

What are the symptoms of bladder stones?

Some bladder stones pass out of the body with urine and don’t cause any symptoms. Large bladder stones can irritate the bladder and cause severe pain, bleeding, and problems urinating. Signs and symptoms include:

  • Changes in urine color: You may have cloudy or dark urine, or you may see blood in your urine.
  • Frequent need to urinate: You may feel like you always need to pee, even if you just went.
  • Pain: With bladder stones, it’s common to feel pain or burning when urinating. You may also feel pain that comes and goes in the lower part of the abdomen (belly). Men sometimes feel pain in the penis or testicles.
  • Stopping and starting: You may have a difficult time starting the flow of urine, even if you really have to go. Sometimes the urine stream stops and starts (urinary intermittency).
  • Urinary tract infections: Bladder stones can lead to infections of the urinary tract (UTIs). UTI symptoms include frequent, painful urination as well as cloudy, smelly urine.

What causes bladder stones?

Bladder stones form when urine sits in the bladder too long. The bladder is part of the body’s urinary system. When urine stays too long in the bladder, it becomes concentrated. Minerals in the urine harden and form crystals that clump together.

This process happens when you aren’t able to empty the bladder completely. Several conditions and factors increase the risk of bladder stones, including:

  • Augmentation cystoplasty: During an augmentation cystoplasty (bladder augmentation) procedure, providers use tissue from the bowel to make the bladder larger and improve the way it works. Sometimes the procedure can cause pee to pool in the bladder.
  • Bladder diverticula: Pouches or pockets in the bladder make it hard to empty the bladder completely. This condition can occur at birth or it can develop later in life as a result of disease or an enlarged prostate.
  • Dehydration: Water dilutes the minerals in urine and flushes out the bladder. Dehydration (not drinking enough fluids) can lead to bladder stones because minerals build up in concentrated urine.
  • Enlarged prostate: The prostate can get bigger as men age, which puts pressure on the urethra (the tube that carries pee from the kidneys to the bladder). The extra pressure can make it difficult to empty the bladder completely.
  • Fallen bladder: Some women develop a condition called cystocele after childbirth. Weakened walls of the bladder fall into the vagina and block the flow of urine.
  • Kidney stones: Bladder stones are similar to kidney stones. Sometimes a kidney stone can travel from your kidney into your bladder. Usually if the stone can pass into the bladder, it can easily be urinated out of the bladder. Very rarely, in patients who have trouble urinating, the stone can get stuck and get bigger inside the bladder and cause pain and difficulty urinating.
  • Neurogenic bladder: Nerve damage from a spinal cord injury, stroke, other disease disease or congenital abnormality (such as spina bifida) can affect how the bladder works. People with neurogenic bladder often need a catheter (a thin, flexible tube) to drain the bladder. Sometimes catheters can’t drain all of the urine.
  • Medical devices. Patients with devices in the bladder, such as catheters, can develop bladder stones from crystals that form on the device. This is typically if the device has been in the body longer than the recommended time periods.

Last reviewed by a Cleveland Clinic medical professional on 09/30/2020.


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