When a stone blocks urine flow, urine can back up toward the kidney. On imaging, this backup of urine may be described as hydronephrosis, which means swelling of the kidney’s collecting system due to impaired drainage.
This obstruction increases pressure inside the kidney’s collecting system. If the obstruction is severe or prolonged, the pressure can affect kidney tissue and reduce filtration by the nephrons, which may raise creatinine, lower estimated glomerular filtration rate (eGFR), and increase the risk of kidney injury.
At Florida Kidney Physicians, treatment planning is based on the patient’s symptoms, imaging results, kidney function, eGFR, creatinine level, infection risk, and the type of stone when that information is available. In many cases, kidney stone care involves both a nephrologist, who helps evaluate kidney function and stone prevention, and a urologist, who performs procedures when stones need to be removed, drained, or broken apart.
When Kidney Stones May Need Urgent Care
Some kidney stones can be monitored safely, but certain symptoms require prompt medical attention.
Seek urgent medical care if you have:
- Fever or chills
- Severe pain that does not improve
- Persistent nausea or vomiting
- Difficulty urinating or inability to urinate
- Decreased urine output
- Blood in the urine with worsening symptoms
- Confusion, weakness, or signs of severe illness
- Signs of dehydration
- Known kidney disease, a single kidney, kidney transplant, or pregnancy
- Symptoms of a urinary tract infection along with kidney stone pain
A kidney stone that blocks urine flow while an infection is present can become a medical emergency. In this situation, antibiotics alone may not be enough. Urgent drainage of the kidney may be needed to relieve pressure, control infection, and protect kidney function.
People with one kidney, a kidney transplant, advanced chronic kidney disease, or significantly reduced eGFR may need faster evaluation because even a short period of obstruction can have greater consequences for kidney function.
In emergency situations, the first step may be temporary drainage with a ureteral stent or nephrostomy tube. This helps urine drain from the kidney and allows infection, pain, or kidney function problems to be stabilized before definitive stone treatment.
How Doctors Choose a Kidney Stone Treatment
There is no single treatment that is right for every kidney stone. The best option depends on several clinical factors.
Imaging tests, such as ultrasound or CT scan, help the care team estimate stone size, location, degree of blockage, and, in some cases, stone density. These details are important when deciding whether observation, medication, temporary drainage, or a procedure is safest.
| Factor | Why It Matters |
|---|---|
| Stone size | Stones under 5 mm are more likely to pass naturally. Stones larger than 10 mm are less likely to pass without intervention and often require urologic evaluation. |
| Stone location | A stone in the kidney may be managed differently than a stone stuck in the ureter. Distal ureteral stones, located closer to the bladder, may pass differently than stones higher in the ureter. |
| Pain severity | Uncontrolled pain may require urgent evaluation, stronger pain control, imaging, or intervention. |
| Infection risk | Fever, chills, or infection with obstruction can be dangerous and may require urgent drainage and antibiotics. |
| Kidney function | Creatinine and estimated glomerular filtration rate (eGFR) help show how well the kidneys are filtering. A blocked stone can sometimes cause an acute decline in kidney function. |
| Stone density | Stone density describes how hard the stone appears on imaging, usually on a CT scan. Denser stones may be harder to break with shock wave lithotripsy. |
| Stone type | Calcium oxalate, uric acid, struvite, and cystine stones may require different prevention strategies. |
Conservative Management: When a Stone May Pass Naturally
Some kidney stones can pass without a procedure. This is more likely when the stone is small, symptoms are controlled, there is no infection, kidney function is stable, and urine is still draining properly.
Stone size is important, but location also matters. A smaller stone located closer to the bladder may pass more easily than a similar-sized stone higher in the ureter near the kidney.
Conservative management may include hydration guidance, pain control, observation, and follow-up testing.
Hydration Guidance
Fluids may help support urine flow and reduce the concentration of minerals in the urine. However, patients should follow their clinician’s advice. Drinking excessive amounts of water is not safe for everyone, especially for people with heart failure, advanced kidney disease, low sodium levels, or fluid restrictions.
For many patients with recurrent stones, long-term prevention may include a goal of producing enough urine each day to reduce stone-forming concentration. This goal should be individualized based on kidney function, heart health, medications, and the patient’s overall condition.
Pain Control
Kidney stone pain can be intense because the stone may irritate or block part of the urinary tract. Pain control may include over-the-counter or prescription medication depending on the patient’s health history.
Patients should not assume that all pain relievers are safe. Some medications, including nonsteroidal anti-inflammatory drugs (NSAIDs), may not be appropriate for people with reduced kidney function, certain stomach conditions, blood thinner use, heart disease, uncontrolled blood pressure, or other medical concerns.
Observation and Follow-Up
If a stone is expected to pass, the care team may recommend follow-up imaging, urine testing, and symptom tracking. Monitoring helps confirm whether the stone has moved, passed, or continued to block urine flow.
Patients should contact their care team if pain worsens, fever develops, vomiting prevents hydration, urine output decreases, or symptoms do not improve.
Medical Therapy for Kidney Stones
Medication may be used to help manage symptoms, support stone passage in selected cases, or reduce the risk of future stones.
The Role of Alpha Blockers, Such as Tamsulosin, in Ureteral Stone Passage
Alpha blockers are medications that relax smooth muscle in the ureter. This may help some ureteral stones move more easily toward the bladder.
The benefit is not the same for every stone. Alpha blockers are most commonly considered for selected patients with distal ureteral stones, especially stones in the 5 to 10 mm range, when conservative management is otherwise appropriate.
In some settings, using alpha blockers for stone passage may be considered an off-label use, meaning the medication is being used based on clinical evidence and guideline-supported practice rather than its original approval purpose.
These medications may not be appropriate for patients with low blood pressure, dizziness, certain medication interactions, or other health concerns. A clinician should decide whether medical expulsive therapy is safe and reasonable.
Pain Management Medications
Some patients need prescription pain medication for severe kidney stone pain. The safest choice depends on kidney function, creatinine level, eGFR, other medical conditions, current medications, and the severity of symptoms.
Pain medication does not remove the stone. It helps control symptoms while the stone passes or while a procedure is planned.
Medications to Prevent Future Stones
Prevention medication depends on the stone type and urine chemistry. A nephrologist may recommend blood tests, stone analysis, and a 24-hour urine collection to understand why stones are forming.
Depending on the results, prevention may include:
- Potassium citrate for certain patients with low urine citrate, acidic urine, or some uric acid stones
- Thiazide diuretics for selected patients with high urine calcium
- Allopurinol for certain patients with high uric acid levels or uric acid stones
- Other targeted treatments for less common stone types, such as cystine or struvite stones
Unlike most calcium stones, some uric acid stones may respond to urine alkalinization, which means raising urine pH with medication such as potassium citrate under medical supervision. This approach depends on the stone type, urine pH, kidney function, blood potassium levels, and the reason stones are forming.
Potassium citrate requires medical supervision. Patients with chronic kidney disease, reduced eGFR, certain heart conditions, or medications that raise potassium may need careful monitoring of blood potassium levels. Too much potassium in the blood, called hyperkalemia, can affect heart rhythm and become dangerous.
Patients should not start potassium citrate or potassium-containing supplements on their own. The dose and safety depend on kidney function, blood potassium levels, urine pH, medications, and the reason stones are forming.
Procedures for Kidney Stones
A procedure may be recommended if the stone is too large to pass, causes ongoing pain, blocks urine flow, is associated with infection, affects kidney function, or has not passed after a period of observation.
In an infected obstructed system, the first priority may be drainage rather than immediate stone removal. Once infection, pressure, and kidney function are stabilized, the care team can plan definitive treatment.
Extracorporeal Shock Wave Lithotripsy
Definition: Extracorporeal shock wave lithotripsy, often called ESWL or shock wave lithotripsy, is a non-invasive procedure that uses shock waves from outside the body.
How it works: The shock waves are directed toward the stone to break it into smaller fragments. These fragments may then pass through the urinary tract in the urine.
When it may be used: ESWL may be considered for selected kidney or ureteral stones depending on size, location, stone density, body anatomy, bleeding risk, and other factors.
Important limitations: Stone density refers to how hard the stone appears on imaging, usually on a CT scan. Denser stones may be harder to break with shock wave lithotripsy, so another procedure may sometimes be recommended. ESWL may not be ideal for very large stones, very hard stones, certain stone locations, pregnancy, untreated infection, or some bleeding conditions.
Ureteroscopy
Definition: Ureteroscopy is a procedure in which a urologist passes a thin scope through the urethra and bladder into the ureter or kidney.
How it works: The stone may be removed directly or broken into smaller pieces with a laser. The goal is to clear the obstruction, remove stone material, and improve urine flow.
When it may be used: Ureteroscopy is commonly used for stones in the ureter and some stones in the kidney. A temporary ureteral stent may be placed afterward to help urine drain while swelling improves.
Important limitations: Ureteroscopy usually requires procedural planning and anesthesia. Some patients may feel discomfort, urinary urgency, or bladder irritation from a temporary stent.
Percutaneous Nephrolithotomy
Definition: Percutaneous nephrolithotomy, or PCNL, is a procedure usually used for larger, complex, or difficult kidney stones.
How it works: The urologist makes a small incision in the back to access the kidney directly. Specialized instruments are used to remove or break apart the stone.
When it may be used: PCNL may be recommended when the stone burden is large, when stones are complex, or when other approaches are less likely to clear the stone effectively.
Important limitations: PCNL is more invasive than ESWL or ureteroscopy, but it can be the most effective option for certain large kidney stones.
Comparing Common Kidney Stone Treatment Options
| Treatment Option | How It Works | When It May Be Considered |
|---|---|---|
| Observation | The stone is monitored while the patient manages symptoms and waits to see if it passes. | Small stones, controlled symptoms, no infection, stable eGFR and creatinine, and no dangerous blockage. |
| Alpha blocker therapy | Relaxes the ureter to help selected ureteral stones pass more easily. | Some distal ureteral stones, especially 5 to 10 mm, when conservative management is otherwise appropriate. |
| Temporary drainage | A ureteral stent or nephrostomy tube helps urine drain from the kidney. | Obstruction with infection, worsening kidney function, severe hydronephrosis, or urgent need to relieve pressure. |
| Shock wave lithotripsy | Uses shock waves from outside the body to break the stone into smaller fragments. | Selected kidney or ureteral stones based on size, location, density, anatomy, and safety factors. |
| Ureteroscopy | Uses a thin scope to reach, remove, or break the stone with a laser. | Stones in the ureter or kidney that need direct treatment, especially if they are stuck or unlikely to pass. |
| PCNL | Removes or breaks up stones through a small incision in the back. | Large, complex, or difficult kidney stones. |
When a Treatment May Be Less Suitable
| Treatment | May Be Less Suitable When |
|---|---|
| Observation | There is infection, uncontrolled pain, worsening kidney function, significant obstruction, or reduced urine output. |
| Alpha blocker therapy | There is low blood pressure, dizziness risk, medication interaction, or a stone that is not in the ureter. |
| Shock wave lithotripsy | The stone is very dense, very large, associated with untreated infection, or the patient has pregnancy or certain bleeding risks. |
| Ureteroscopy | The patient is not ready for anesthesia or procedural planning, or when temporary stent discomfort is a major concern. |
| PCNL | The stone burden does not justify a more invasive procedure or when surgical risks outweigh expected benefits. |
Preventing Future Kidney Stones
Treatment does not end once a stone passes or is removed. Because kidney stones can recur, prevention is an important part of treatment, especially for patients who have had more than one stone, have a strong family history, have chronic kidney disease, or have abnormal urine or blood test results.
Prevention may include:
- Stone analysis to identify the stone type
- Blood tests to check kidney function, creatinine, calcium, uric acid, potassium, and other factors
- 24-hour urine testing to measure urine volume, calcium, oxalate, citrate, sodium, uric acid, urine pH, and other stone-related markers
- Personalized nutrition guidance based on the type of stone and urine results
- Medication when needed to correct specific urine chemistry problems
Diet advice should not be one-size-fits-all. For example, some patients may need to reduce sodium, adjust animal protein intake, manage oxalate intake, increase citrate-rich foods, or take medication.
One common mistake is reducing dietary calcium too much. For many patients with calcium oxalate stones, getting an appropriate amount of calcium from food can actually help reduce stone risk. Calcium in the digestive tract can bind oxalate from food, which may reduce how much oxalate reaches the urine. This does not mean that every patient should take calcium supplements. Calcium intake should be discussed with a clinician or renal dietitian, especially for patients with chronic kidney disease or abnormal calcium levels.
Patients should tell their care team about supplements, including vitamin C, calcium supplements, protein powders, herbal products, or “detox” products. Some supplements may increase stone risk or may not be safe for people with reduced kidney function.
Struvite stones are often related to certain urinary tract infections and usually require careful urologic and medical management rather than diet changes alone.
Why Kidney Stone Prevention Should Be Personalized
Kidney stones can form for different reasons. Two patients may both have calcium oxalate stones, but one may have low urine volume, another may have high urine calcium, another may have low citrate, and another may have high oxalate.
High urine calcium, high urine oxalate, low urine citrate, high urine sodium, acidic urine pH, and low urine volume can each contribute to stone risk in different ways.
That is why prevention is usually strongest when it is guided by biomarkers, including:
- Urine volume
- Urine calcium
- Urine oxalate
- Urine citrate
- Urine sodium
- Urine uric acid
- Urine pH
- Blood creatinine and eGFR
- Blood calcium and potassium
A nephrology-guided prevention plan helps connect the stone type, urine chemistry, kidney function, diet, medications, and long-term risk.
What Not to Do Without Medical Guidance
Patients should not try to force a stone to pass by drinking excessive amounts of water, taking leftover antibiotics, using unapproved supplements, stopping prescribed medications, or delaying care when symptoms are severe.
Home care may be appropriate for selected stones, but only when infection, dangerous obstruction, and kidney function problems have been ruled out.
Patients should also avoid assuming that online remedies, “stone dissolving” supplements, detox products, or high-dose vitamins are safe. Some products may interact with medications, worsen kidney function, or increase stone risk.
Shared Decision-Making
Kidney stone treatment often involves choices. Some patients may be able to wait for a stone to pass. Others may benefit from a procedure sooner. The care team should explain the expected benefits, risks, recovery time, and follow-up needs for each option.
Patients can prepare for the discussion by asking:
- How large is my stone?
- Where is the stone located?
- Is it still in the kidney, or has it moved into the ureter?
- Is it blocking urine flow?
- Do I have hydronephrosis?
- Is there any sign of infection?
- What are my creatinine and eGFR?
- Is it likely to pass on its own?
- Would an alpha blocker such as tamsulosin be appropriate for my case?
- Would I need temporary drainage before definitive treatment?
- What are the benefits and risks of each treatment option?
- What should I do if symptoms get worse?
- How can I reduce my risk of another stone?
After the stone passes or is removed, patients may also ask:
- Was the stone sent for analysis?
- Do I need a 24-hour urine test?
- Should my diet change based on my urine results?
- Do I need follow-up imaging?
- Am I at higher risk because of CKD, medications, family history, or recurrent stones?
Personalized Kidney Stone Care
Kidney stones can be painful and stressful, but patients do not have to navigate treatment alone. At Florida Kidney Physicians, our best nephrology team helps evaluate kidney function, identify risk factors for recurrent stones, coordinate care when procedures are needed, and build prevention plans based on each patient’s medical history and test results.
When a procedure is needed, urology is often central to removing, draining, or breaking the stone. Nephrology plays an important role in protecting kidney function, identifying why stones are forming, reducing recurrence risk, and coordinating long-term prevention for patients with recurrent stones, chronic kidney disease, abnormal labs, or complex medical histories.
The goal is not only to treat the current stone, but also to reduce the risk of future stones whenever possible.
FAQs
Can kidney stones pass on their own?
Yes, some kidney stones can pass on their own, especially when they are small, not causing infection, not blocking urine flow dangerously, and kidney function is stable. Stones under 5 mm are generally more likely to pass naturally, but a clinician should determine whether observation is safe.
When does a kidney stone need a procedure?
A kidney stone may need a procedure if it is too large to pass, causes uncontrolled pain, blocks urine flow, is linked to infection, affects kidney function, or does not pass after a period of monitoring.
Do alpha blockers such as tamsulosin work for all kidney stones?
No. Alpha blockers may help selected ureteral stones pass more easily, especially distal ureteral stones between 5 and 10 mm. In some settings, this may be considered an off-label use. They are not appropriate for every stone or every patient.
What is the difference between shock wave lithotripsy and ureteroscopy?
Shock wave lithotripsy uses shock waves from outside the body to break a stone into smaller pieces. Ureteroscopy uses a thin scope passed through the urinary tract to reach the stone directly, where it can be removed or broken apart with a laser.
Why would I need a ureteral stent for a kidney stone?
A ureteral stent is a small tube placed by a urologist to help urine drain from the kidney to the bladder. It may be used when a stone is blocking urine flow, after ureteroscopy, or when swelling could temporarily interfere with drainage.
When should I go to the emergency room for a kidney stone?
Seek emergency care if you have fever, chills, severe or worsening pain, repeated vomiting, trouble urinating, decreased urine output, confusion, weakness, or kidney stone symptoms with a known single kidney, kidney transplant, pregnancy, or advanced kidney disease.
Do all kidney stones need surgery?
No. Some small stones can pass with observation, symptom control, and follow-up. Surgery or another procedure may be needed when a stone is large, stuck, infected, blocking urine flow, affecting kidney function, or unlikely to pass safely.
Can reducing calcium prevent calcium oxalate kidney stones?
Not usually. For many patients with calcium oxalate stones, getting an appropriate amount of calcium from food can help reduce oxalate absorption in the digestive tract. Patients should not start a low-calcium diet or calcium supplements without medical guidance.
Is potassium citrate safe for everyone with kidney stones?
No. Potassium citrate can help selected patients, but it requires medical supervision. People with chronic kidney disease, reduced eGFR, high potassium levels, certain heart conditions, or medications that raise potassium may need close blood monitoring.
How can I prevent kidney stones from coming back?
Prevention depends on the type of stone and your urine chemistry. Your care team may recommend stone analysis, bloodwork, a 24-hour urine test, diet changes, hydration goals, or medication based on your individual results.