Kidney Stone: Symptoms, Causes and Treatment

📖 9 min read Written/reviewed by Dr. Alhad Naragude, MBBS, MS, DrNB Urology Last updated: June 17, 2026

A kidney stone is a hard deposit formed from minerals and salts in urine. It may remain silently inside the kidney or move into the ureter, the narrow tube carrying urine from the kidney to the bladder. When a stone blocks urine flow, it can cause sudden severe side pain, vomiting, burning urination or blood in urine. Small stones may pass with medicines and observation, but stones causing fever, blockage, uncontrolled pain or kidney function risk need urgent urology evaluation. Fever with kidney stone pain is an emergency.

What is a kidney stone?

A kidney stone is a solid crystal-like deposit that forms when urine becomes concentrated and minerals start sticking together. Stones can form inside the kidney and may later move into the ureter, bladder or urinary passage.

Not every kidney stone causes pain. Many patients are surprised when an ultrasound shows a stone even though they have no symptoms. Pain usually starts when the stone moves, irritates the urinary tract or blocks urine flow.

In OPD, the most important decision is not only the stone size. A urologist checks whether the stone is causing blockage, infection, kidney swelling, repeated symptoms or kidney function risk.

Kidney stone symptoms, causes and treatment: quick answer

Kidney stone symptoms depend on the stone’s size, location and whether it is blocking urine flow. A small stone stuck in the ureter can cause severe pain, while a larger stone sitting quietly inside the kidney may cause no pain.

Symptom	What it may suggest
Severe side or back pain	Ureter blockage or kidney swelling
Pain going to groin or testis	Stone moving down the ureter
Nausea or vomiting	Common with severe renal colic
Burning urination	Lower ureteric stone or infection
Frequent urge to pass urine	Stone near bladder end
Blood in urine	Stone irritation, but other causes must also be ruled out
Fever or chills	Possible infection with blockage — emergency
Reduced urine output	Needs urgent evaluation

NIDDK lists sharp pain in the back, side, lower abdomen or groin, blood in urine, constant urge to urinate, painful urination, inability to urinate or passing only a small amount, and cloudy or bad-smelling urine as possible symptoms of kidney stones.

Why does kidney stone pain come suddenly?

Kidney stone pain often starts suddenly because the stone blocks urine flow. The kidney continues to produce urine, but urine cannot pass freely through the ureter. This creates pressure and stretching in the kidney and ureter, causing severe cramping pain.

This pain may come in waves. Many patients feel restless and cannot find a comfortable position. Vomiting can also happen during severe kidney stone pain.

What causes kidney stones?

Kidney stones form when the balance of water, minerals, salts and stone-preventing substances in urine changes.

Common causes and risk factors include:

Drinking less water.
Heavy sweating without enough fluid replacement.
High salt intake.
Excess animal protein in some patients.
Low urine citrate, which normally helps reduce stone formation.
High urinary calcium, oxalate or uric acid.
Recurrent urinary infection.
Family history of kidney stones.
Obesity, diabetes or metabolic syndrome.
Certain bowel diseases or previous bariatric surgery.
Some medicines or supplements.

Do not completely stop calcium in food unless your doctor specifically advises it. Many calcium stone patients still need normal dietary calcium, while reducing excess salt and improving hydration. NIDDK notes that prevention may involve drinking enough water, diet changes and medicines depending on the patient’s stone risk.

Types of kidney stones

Stone type	Common association
Calcium oxalate stone	Most common type; linked with low fluid intake, high urine oxalate or calcium, high salt intake and metabolic factors
Calcium phosphate stone	May be associated with certain urine chemistry problems
Uric acid stone	More likely with persistently acidic urine; may be linked with gout, obesity or metabolic syndrome
Struvite stone	Usually related to recurrent urinary infection
Cystine stone	Rare; usually due to an inherited condition

Stone analysis is useful, especially if you have repeated stones, stones in both kidneys, young age at first stone or a family history of stones.

When should you see a urologist?

See a urologist if you have:

Severe side or back pain.
Stone seen on ultrasound, X-ray or CT scan.
Blood in urine.
Repeated stone episodes.
Fever, chills or urine infection with stone.
Vomiting or inability to drink fluids.
Kidney swelling on ultrasound.
Raised creatinine or kidney function concern.
Single functioning kidney.
Stone that has not passed despite medicines.
A DJ stent placed previously that needs follow-up or removal.

Pain relief does not always mean the stone has passed. Sometimes the pain reduces, but the stone continues to block the kidney silently. Follow-up imaging is important when advised.

Emergency warning signs

A kidney stone can become dangerous if it blocks urine and infection develops behind the blockage.

Seek urgent medical care if you have:

Fever, chills or shivering with stone pain.
Severe pain not settling with prescribed medicines.
Repeated vomiting.
Reduced urine output or inability to pass urine.
Stone with a single kidney.
Pregnancy with suspected stone.
Diabetes with fever or urine infection symptoms.
Known kidney disease or rising creatinine.
Confusion, weakness, drowsiness or low blood pressure.

Stone with infection is especially risky in patients with diabetes, older age, weak immunity or kidney disease. EAU guidance highlights immediate evaluation when renal colic occurs with fever, solitary kidney or diagnostic uncertainty.

Do not keep self-medicating for kidney stone pain

Many patients take painkillers repeatedly during stone pain and delay evaluation. This can be risky.

Do not keep taking painkillers again and again without medical advice, especially if you have vomiting, dehydration, fever, diabetes, high BP, kidney disease, reduced urine output or raised creatinine. Some painkillers can affect kidney function in dehydrated or high-risk patients.

Pain control is important, but it should not hide a dangerous stone blockage or infection.

Tests used to diagnose kidney stones

Your urologist may advise tests based on pain severity, fever, kidney function and suspected blockage.

Urine routine and microscopy

This checks for blood cells, pus cells, crystals and signs of infection.

Urine culture

This is important if there is fever, pus cells in urine, recurrent UTI or planned stone surgery.

Serum creatinine

This blood test checks kidney function.

Ultrasound KUB

Ultrasound can detect kidney swelling, kidney stones and bladder urine. It is useful as a first test, especially when radiation needs to be avoided.

X-ray KUB

Some calcium stones are visible on X-ray. But not all stones can be seen on X-ray.

CT KUB / NCCT KUB

Non-contrast CT KUB is often the most accurate test for stone size, location, density and obstruction. It helps decide whether observation, URSL, RIRS, PCNL or another treatment is suitable.

Stone analysis and metabolic evaluation

These are important in recurrent stones, bilateral stones, young patients, family history, unusual stone type or high-risk patients.

How a urologist decides treatment

Treatment depends on stone size, stone location, pain severity, infection, kidney swelling, kidney function, previous stone history and patient preference.

Situation	Common treatment approach
Small stone, controlled pain, no fever, stable kidney function	Observation, medicines and follow-up
Lower ureteric stone with good chance of passage	Medicines and observation in selected patients
Ureteric stone with severe pain, blockage or failure to pass	URSL may be advised
Kidney stone suitable for flexible scope treatment	RIRS may be advised
Larger or complex kidney stone	PCNL may be advised
Selected stone suitable for shock wave treatment	ESWL may be considered
Stone with fever/infection and blockage	Urgent drainage first, stone treatment later

EAU guidelines describe shock wave lithotripsy, PCNL and RIRS as available treatment options for kidney stones, with outcomes influenced by stone size and location.

Kidney stone treatment options

1. Observation and medicines

Small stones may pass naturally if pain is controlled, there is no fever, kidney function is stable and the stone is likely to pass.

Medicines may be used for pain control, nausea control and, in selected ureteric stones, to help the stone pass. Follow-up imaging is important because symptom improvement does not always confirm stone passage.

2. URSL for ureteric stones

URSL means ureterorenoscopy with laser lithotripsy. A small scope is passed through the urinary passage into the ureter. The stone is broken with laser and fragments are removed or allowed to pass.

A temporary DJ stent may be placed after the procedure. URSL is commonly used when a ureteric stone is stuck, painful, causing obstruction or unlikely to pass.

3. RIRS for kidney stones

RIRS means retrograde intrarenal surgery. A flexible scope is passed through the urinary passage into the kidney. A laser is used to dust or fragment the stone.

RIRS is often used for selected kidney stones, especially when a cut on the body is not preferred. A temporary DJ stent may be needed after the procedure.

4. PCNL for larger kidney stones

PCNL means percutaneous nephrolithotomy. A small tract is made from the back into the kidney to remove larger or complex stones.

PCNL is usually preferred for larger kidney stones, multiple stones or stones where RIRS or ESWL may not clear the stone effectively.

5. ESWL / shock wave lithotripsy

ESWL uses shock waves from outside the body to break selected stones into smaller fragments. These fragments then pass in urine.

ESWL works best for suitable stone size, location and density. Some patients may need repeat sessions or another procedure.

6. Emergency drainage: DJ stent or nephrostomy

If a stone causes blockage with infection, the first step may be urgent drainage, not immediate stone removal.

Drainage may be done with a DJ stent from below or a nephrostomy tube from the back. The stone is treated later after infection settles.

NICE guidance covers assessment and management of renal and ureteric stones, including shock wave treatment, ureteroscopy and PCNL in appropriate situations.

Recovery after kidney stone treatment

Recovery depends on the procedure and stone burden.

After URSL or RIRS, some patients have burning urination, mild blood in urine, frequency, urgency and stent-related discomfort for a few days. These symptoms are usually manageable but should be discussed if severe.

After PCNL, hospital stay and recovery may be longer because the stone burden is often larger. Follow-up imaging may be needed to check stone clearance and kidney drainage.

A DJ stent is temporary. It should be removed on the date advised by your urologist. Forgotten stents can cause infection, stone formation and complications.

Can kidney stones come back?

Yes. Kidney stones can recur. Surgery removes the current stone, but it does not automatically prevent the next one.

The goal is not just to remove this stone, but to reduce the chance of the next stone.

General prevention steps include:

Drink enough fluids to keep urine pale, unless your doctor has advised fluid restriction.
Reduce excess salt.
Avoid dehydration during summer, travel and heavy sweating.
Do not stop dietary calcium without medical advice.
Avoid unnecessary vitamin C or calcium supplements unless prescribed.
Maintain healthy weight and regular physical activity.
Treat recurrent urine infection properly.
Follow stone-specific diet advice when stone analysis or urine testing is available.

NIDDK notes that prevention may include drinking enough water, diet changes and medicines, depending on the person’s stone risk.

FAQs

What are the common symptoms of kidney stone?

Common symptoms include severe side or back pain, pain going to the groin, nausea, vomiting, burning urination, frequent urination and blood in urine. Fever with stone pain needs urgent care.

Can a kidney stone be present without pain?

Yes. A stone inside the kidney may cause no pain and may be found on ultrasound or CT scan done for another reason.

Does kidney stone size decide treatment?

Stone size is important, but location, blockage, infection, kidney swelling, kidney function and pain severity are also important. A small ureteric stone can sometimes cause more pain than a larger silent kidney stone.

Can medicines dissolve kidney stones?

Most kidney stones do not dissolve with medicines. Some uric acid stones may dissolve with urine alkalinisation under medical supervision. Calcium stones usually need observation, procedure or prevention strategy depending on the case.

When is kidney stone an emergency?

Kidney stone becomes an emergency when there is fever, chills, repeated vomiting, reduced urine output, single kidney, pregnancy, kidney failure risk or uncontrolled pain.

Which is better: URSL, RIRS or PCNL?

URSL is commonly used for ureteric stones. RIRS is used for selected kidney stones. PCNL is usually preferred for larger or complex kidney stones. The best option depends on CT findings and patient factors.

Can kidney stones come back after surgery?

Yes. Stones can come back even after successful surgery. Prevention needs hydration, diet correction, stone analysis and follow-up in recurrent stone formers.

Should I drink a lot of water during kidney stone pain?

Hydration is important, but forcing large amounts of water during severe pain or vomiting may worsen discomfort. If you have fever, vomiting, reduced urine or severe pain, seek medical care.