Overview
Kidney stones are hard deposits that form in the kidneys from substances in urine. Small stones may pass on their own, but a stone can block urine flow and cause severe pain, infection, or kidney problems.
How common is it?
Kidney stones are common. Some people have one stone only, while others get them again and benefit from finding out which type of stone they had.
Causes and risk factors
Stones form when urine becomes concentrated or contains higher levels of certain minerals and salts. Not drinking enough fluid is a common contributor. Infection, some medical conditions, family history, diet, and certain medicines can also increase risk.
Common risk factors
- Having had a kidney stone before or having a family history
- Not drinking enough fluid or losing fluid through vomiting, diarrhoea, or sweating
- Repeated urine infections, bowel disease or surgery, obesity, gout, or certain hormone conditions
- Some medicines or supplements; ask a clinician or pharmacist before changing anything
Symptoms
- Sharp pain in the side or back that may move to the lower tummy or groin
- Pain that comes in waves
- Feeling or being sick
- Blood in the urine
- Needing to pass urine more often or pain when passing urine
When to see a doctor
Seek urgent medical help if you have severe pain, fever or chills, vomiting that stops you keeping fluids down, trouble passing urine, or you feel very unwell. These can be signs of a blocked kidney or infection. Get prompt advice for blood in the urine or pain that does not settle.
Diagnosis
Tests can include urine and blood tests, and a scan such as a CT scan or ultrasound. If you pass a stone, keep it if possible and ask whether it should be analysed; this can help guide prevention.
Treatments
Pain and symptom relief
Small stones may be managed with pain relief, anti-sickness medicine, and advice about fluid intake. Anti-inflammatory painkillers are not suitable for everyone, especially with some kidney, stomach, heart, pregnancy, or blood-thinning conditions.
Helping a stone pass
A clinician may offer a medicine that relaxes the ureter for some stones. Do not take treatment borrowed from someone else.
Procedures
Larger, blocked, infected, or persistent stones may need hospital treatment such as shock-wave treatment, a camera procedure, or surgery.
Self-care and lifestyle
- Drink fluids regularly unless you have been advised to restrict them
- Do not force large amounts of fluid if it worsens severe pain or vomiting; seek advice instead
- Follow individual prevention advice after stone analysis or specialist review
- Do not start high-dose supplements or restrictive diets for stones without professional advice
Prevention
Drinking enough fluid to keep urine pale can help many people, but prevention should be tailored to the stone type and other health conditions. Your team may suggest dietary changes or medicine after testing.
Sources and review
Last reviewed: 1 August 2026 by Living Diabetes Editorial Team. This guide was checked against current patient and professional guidance. It is educational and does not replace care from your own healthcare team.