What Are They?
Kidney and bladder stones are hard lumps made of minerals and salts that form in the urinary system. They can develop in the kidneys (where urine is made) or the bladder (where urine is stored before passing out of the body). These stones can vary in size — from tiny grains to larger stones that can block the flow of urine and cause significant discomfort.
What Causes Stones?
Stones form when certain substances in the urine — like calcium, oxalate, or uric acid — become too concentrated and start to stick together. Common causes include:
- Not drinking enough water
- Diets high in salt or protein
- Family history of stones
- Certain medical conditions (e.g. gout, urinary tract infections)
- Some medications or supplements
Common Symptoms
Some people have stones without any symptoms, especially if they’re small. However, when stones move or block the flow of urine, symptoms can include:
- Severe pain in the lower back, side, or abdomen
- Pain during urination
- Frequent urge to urinate
- Blood in the urine (urine may appear pink or red)
- Nausea or vomiting
- Cloudy or foul-smelling urine
- Infection or fever if a stone causes a blockage
How Are Stones Treated?
Treatment depends on the size, location, and type of stone, as well as the severity of symptoms.
- Small stones
- May pass naturally with plenty of fluids, pain relief, and time
- You may be asked to strain your urine to catch the stone for analysis
- Larger stones or those causing symptoms may need treatment such as:
- Shock wave therapy (ESWL) – breaks the stone into smaller pieces
- Ureteroscopy – a thin scope is passed into the urinary tract to remove or break the stone
- Percutaneous nephrolithotomy – keyhole surgery for large kidney stones
- Bladder stone removal – often using a scope and laser to break the stone
- Treating the underlying cause
- Blood and urine tests help determine what type of stone you have
- You may be advised on diet or medications to prevent stones from coming back
Preventing Stones
To lower your risk of future stones:
- Drink plenty of fluids, especially water
- Eat a balanced diet low in salt and animal protein
- Limit foods high in oxalates (e.g. spinach, nuts) if you are prone to certain types of stones
- Follow any personalised advice from your doctor or specialist