Kidney stones are rock-like masses of crystals that form in the kidneys. They can be painful and sometimes serious. It is important to see your doctor if you think you might have a kidney stone.
Some medications, such as antiviral drugs, can increase your risk.
But for most people, it is not known why they happen.
There are many types of kidney stones, but most often they are made from calcium. They can range from in size as small as a grain of sand to as big as a golf ball.
Kidney stone pain
The pain of kidney stones can be severe, although some people feel no pain. If you have a kidney stone, you usually feel the pain in your back, side, lower belly or groin. It is caused by the stone passing from the kidney to the bladder, or from the bladder to the outside world.
Kidney stone symptoms
If you have kidney stones, you may also:
- have blood in your urine
- feel sick
- have a fever, hot and cold shivers or sweats
- feel like you have gravel in your urine
- feel like you need to pass urine often or urgently
Kidney stones diagnosis
Kidney stones can be found by chance during tests for other conditions, if your doctor thinks you might have kidney stones, tests include urine tests, blood tests and scans such as an simple x-ray and an ultrasound.
The Australasian College for Emergency Medicine recommends that a CT scan may not always be necessary to diagnose kidney stones. Ask your doctor if a CT scan is necessary for you. For further information, visit the Choosing Wisely Australia website.
Kidney stones treatment
You can take simple painkillers like paracetamol if the pain is mild. If the pain is severe, you will need to see your doctor or go to an emergency department.
Ensure you drink adequate amounts of clear fluid such as water.
Most stones are small and come out by themselves in the urine. You can check for stones by urinating through a piece of stocking. If you do catch a stone, keep it in a clean jar so your doctor can find out what it is made from.
A larger stone might need to be removed by a surgeon, who can use ultrasound to break it up, or an operation to remove it.
Some people are also advised to take medicine to make the urine less acidic or antibiotics if there is a kidney or bladder infection.
Preventing kidney stones
You can reduce the risk of getting a kidney stone by:
- drinking plenty of water
- limiting drinks that contain phosphoric acid (which may be used to flavour cola and beer)
- avoiding urinary tract infections and, if you get one, treating it quickly
- limiting your intake of animal protein such as red meat, chicken, seafood and eggs
- drinking fruit juices, especially orange, grapefruit and cranberry
- including dairy foods or alternatives in your diet
- reducing your salt intake
If you have had a stone before, your doctor may advise you about additional treatments to help you avoid getting another one.
For more information, visit the Kidney Health Australia website.
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Last reviewed: October 2020