How kidney stone pain feels and where it shows up
Kidney stone pain typically starts in your flank — the area between your ribs and hip on one side of your back — and often radiates down toward your groin. The pain comes in waves rather than staying constant, building to intense peaks and then easing, sometimes over minutes or hours. Many people describe it as the worst pain they have ever felt, though the intensity varies depending on the stone's size and position in your urinary tract.
The pain pattern matters because it helps distinguish a kidney stone from other causes of flank pain. A stone causes sharp, colicky pain (the wave pattern), while muscle strain or a kidney infection usually produces steady, dull aching. You may also notice that you cannot find a comfortable position — moving around sometimes helps, sometimes makes it worse, and sitting still does not relieve it the way it would with a pulled muscle.
Other signs that point toward a stone include blood in your urine (visible or detected on a test), nausea or vomiting alongside the pain, and an urgent need to urinate more often than usual. Fever is not typical of an uncomplicated stone; if you have fever with flank pain, a kidney infection is more likely.
Key Takeaways
- Kidney stone pain arrives in waves in your flank or lower back, often radiating toward the groin, and is usually sharp rather than steady.
- Blood in urine, nausea, and frequent urination often accompany stone pain, but fever suggests infection rather than a stone.
- A doctor confirms a stone through imaging (CT scan or ultrasound) and urine tests, not by pain description alone.
- Most stones pass on their own within two to four weeks with fluids and pain management, though larger stones may need intervention.
- Seek immediate care if you have fever with flank pain, cannot keep down fluids, or pain is unbearable despite medication.
What your doctor will do to confirm a stone
Your doctor will not diagnose a kidney stone based on your description of pain alone. They will order imaging — usually a CT scan without contrast, which is the fastest and most accurate way to spot a stone, or an ultrasound if CT is not available. The scan shows the stone's size, location, and whether it is blocking urine flow, all of which determine what happens next.
You will also provide a urine sample. The lab checks for blood, infection, and crystals that suggest stone formation. If you have fever or signs of infection, blood tests may follow to check your white blood cell count and kidney function. These results together tell your doctor whether the stone is likely to pass on its own or whether you need intervention.
This workup usually happens in an urgent care or emergency department if your pain is severe, or in your primary care doctor's office if the pain is manageable and you can wait a few days. The imaging itself takes minutes, though getting results may take hours in a busy emergency department.
Pain management while the stone passes
For most stones, the main treatment is time, fluids, and pain control. Your doctor will prescribe or recommend over-the-counter pain relief — often ibuprofen or naproxen for the first line, since these also reduce inflammation in the urinary tract. If those do not work, prescription options include stronger NSAIDs or opioid medications, though opioids carry risks and are used more cautiously now than in the past.
Drinking plenty of water helps flush the stone through your system and reduces the pain of urine passing around it. Most people are told to drink enough to produce clear or pale urine throughout the day. Avoid caffeine and alcohol, which can dehydrate you and make pain worse.
Nausea often accompanies stone pain, making it hard to drink or eat. If you cannot keep fluids down, you may need IV fluids in an urgent care or emergency department. Anti-nausea medication can help you tolerate drinking, which is important for passing the stone.
When a stone needs more than waiting and fluids
Stones smaller than 5 millimeters pass on their own in most cases. Stones between 5 and 10 millimeters pass sometimes, depending on their shape and position. Stones larger than 10 millimeters rarely pass without help. Your doctor will discuss these odds based on your specific stone.
You may also need intervention if the stone is blocking urine flow and causing kidney damage, if you have an infection that cannot be treated while the stone is in place, or if pain is not controlled after several days of medication and fluids. The most common procedure is ureteroscopy, in which a thin camera is threaded up through your urethra to locate and remove or break up the stone. Extracorporeal shock wave lithotripsy (ESWL) uses sound waves to break the stone into smaller pieces that pass more easily, though it is less commonly used now.
These procedures are usually done by a urologist, either in an outpatient surgery center or a hospital. Recovery is typically quick — most people go home the same day — though you may have some blood in your urine and mild discomfort for a few days afterward.
What to expect in the days and weeks after a stone passes
Once the stone passes, pain stops abruptly. You may feel mild discomfort or a burning sensation when urinating for a day or two, but severe pain should not return. Some people pass the stone without realizing it — they simply notice the pain is gone and their urine looks normal again.
Your doctor may ask you to strain your urine (catch it in a filter or strainer) to retrieve the stone for analysis. Knowing what the stone is made of — calcium oxalate, uric acid, struvite, or another compound — helps prevent future stones. This information guides dietary changes or medications that reduce your risk of forming another one.
Follow-up imaging is not always necessary if your pain has resolved and your kidney function is normal. However, if you had a large stone, a blocked kidney, or signs of infection, your doctor may order a follow-up ultrasound or CT scan to confirm everything has cleared.
Preventing another stone
The risk of forming another kidney stone is significant — about half of people who have had one will form another within five to ten years. Prevention depends partly on the stone's composition and partly on your habits.
For most stones, drinking more water is the single most effective prevention. Aim for enough fluid intake that your urine stays pale or clear. Limit salt in your diet, as high sodium increases calcium in your urine. If your stone was calcium oxalate (the most common type), your doctor may recommend limiting foods high in oxalate, such as spinach, nuts, and chocolate, though this is less important than staying hydrated.
If you have had multiple stones or a stone caused by a metabolic problem, your doctor may order blood and urine tests to check for conditions like hyperparathyroidism or high uric acid. Depending on the results, you might take medication to prevent stone formation — for example, allopurinol for uric acid stones or a thiazide diuretic for calcium stones.
When to seek immediate care
Go to an emergency department or call 911 if you have severe pain that does not improve with medication, fever above 101°F along with flank pain, inability to keep down fluids or medications, or signs of kidney damage such as very low urine output or confusion. These situations suggest complications like infection, complete blockage, or kidney injury that need urgent treatment.
If your pain is moderate and you have no fever or other warning signs, urgent care or your primary care doctor's office is appropriate. They can order imaging and start you on pain management while you wait to see a urologist if needed.
Frequently Asked Questions
Can a kidney stone cause pain in the front of my abdomen?
Yes. As a stone moves down the ureter toward the bladder, pain can shift from the flank to the lower abdomen or groin. Pain in the very front center of your abdomen is less typical of a stone and may suggest another problem, so mention the exact location to your doctor.
How long does it take for a stone to pass?
Most stones pass within two to four weeks. Smaller stones (under 5 mm) often pass within a week or two. Larger stones may take longer or not pass at all without intervention. Your doctor can estimate based on the stone's size and position.
Will I need antibiotics if I have a kidney stone?
Antibiotics are not needed for an uncomplicated stone without infection. However, if you have fever, signs of infection, or a blocked kidney with infection, antibiotics are essential and often given before any procedure to remove the stone. Blood and urine tests determine whether infection is present.
Can I work or exercise while passing a stone?
Most people cannot work during acute stone pain — it is too intense. Once pain is controlled with medication, light activity is fine. Strenuous exercise or heavy lifting can wait until after the stone passes. Staying active and drinking water actually helps stones pass, so gentle movement is encouraged.
What if imaging shows a stone but I have no pain?
Asymptomatic stones (found by chance on imaging for another reason) usually do not need treatment unless they are very large, blocking urine flow, or causing kidney damage. Your doctor will monitor you with periodic imaging. Treatment is considered if the stone starts causing problems or grows.