For kidney stone pain, you’ll typically receive anti-inflammatory painkillers as the first treatment, along with anti-nausea medication if needed. Beyond that initial relief, what you’re given depends on the size and type of your stone. Small stones under 4 mm usually pass on their own in about 31 days with pain management at home. Larger stones may need medication to help them pass, or a procedure to break them up or remove them.
Pain Relief in the Emergency Room
Kidney stone pain (renal colic) is notoriously intense, and the ER focuses on controlling it fast. Anti-inflammatory drugs like ketorolac, given through an IV or injection, are the standard first choice. These work just as well as opioid painkillers for kidney stone pain, with fewer side effects like nausea and drowsiness. Acetaminophen given intravenously is another common option. If those aren’t enough, you may receive morphine or another opioid, but doctors generally try anti-inflammatories first.
If you’re vomiting, which is common during a stone episode, you’ll likely get ondansetron through an IV or dissolved under your tongue. You may also receive IV fluids if you’re dehydrated from vomiting, typically a liter of saline. Doctors won’t flood you with extra fluids, though. Aggressive hydration can actually increase pain by stretching the kidney.
Once you’re discharged, you’ll usually go home with oral anti-inflammatories like ibuprofen or naproxen and sometimes a short course of stronger painkillers to get through the worst of it.
Medication to Help a Stone Pass
For stones between 5 and 10 mm stuck in the ureter (the tube connecting your kidney to your bladder), your doctor may prescribe tamsulosin. This medication relaxes the smooth muscle in the ureter, widening the passage so the stone can move through more easily. A large meta-analysis found tamsulosin increased the expulsion rate by about 44% for stones over 5 mm. For stones 5 mm or smaller, it doesn’t seem to make a meaningful difference since most of those pass on their own anyway.
Tamsulosin is typically taken once daily for a few weeks while you wait for the stone to pass. Side effects are mild for most people, mainly dizziness or lightheadedness when standing up quickly.
How Long It Takes to Pass a Stone
Stone size is the biggest factor in whether you’ll pass it naturally and how long you’ll wait:
- Under 4 mm: Most pass on their own in about 31 days.
- 4 to 6 mm: Around 60% pass naturally, taking an average of 45 days.
- Over 6 mm: Only about 20% pass without intervention. Those that do can take up to a year.
During this waiting period, you’ll be drinking plenty of water and managing pain at home. Your doctor will likely ask you to strain your urine so you can catch the stone for lab analysis, which helps determine what caused it and how to prevent the next one.
Procedures for Stones That Won’t Pass
When a stone is too large to pass or is causing complications like infection or kidney damage, you’ll need a procedure. The two most common options for stones under 2 cm are shock wave lithotripsy and ureteroscopy.
Shock wave lithotripsy uses focused sound waves from outside your body to break the stone into smaller fragments that you then pass naturally. It’s noninvasive, and recovery is noticeably easier. Patients experience less pain in the first week, fewer urinary symptoms, and miss less work compared to ureteroscopy. You’re typically sedated or under light anesthesia during the 30 to 60 minute session.
Ureteroscopy involves a thin, flexible scope passed through your urethra and bladder up into the ureter. A laser breaks the stone apart, and the fragments are removed. Stone clearance rates are similar to lithotripsy, but recovery takes longer and the procedure often requires placing a temporary stent (a small tube inside the ureter to keep it open while it heals). About 30% of ureteroscopy patients need a second procedure under anesthesia just to remove that stent, compared to only 3% of lithotripsy patients needing a follow-up.
Lithotripsy does have limits. For stones over 1 cm in the lower part of the kidney, or over 2 cm anywhere in the kidney, it’s less effective. In those cases, doctors recommend a percutaneous approach, where a small incision is made in the back to access the kidney directly and remove the stone. This is the go-to for large stones over 2 cm.
Dissolving Uric Acid Stones
If your stone is made of uric acid (which accounts for roughly 10% of kidney stones), you may be able to dissolve it without any procedure at all. Uric acid stones form when urine is too acidic, so the treatment involves raising your urine pH to between 6.5 and 7.0, which makes conditions hostile to the stone and promotes it breaking down.
Potassium citrate is the most commonly prescribed medication for this. You take it in divided doses throughout the day and periodically test your urine pH at home with test strips to make sure you’re in the target range. Sodium bicarbonate is an alternative. The process requires patience and monitoring, but it can eliminate stones entirely without surgery.
Preventing the Next Stone
About half of people who get a kidney stone will get another one within five to ten years, so prevention is a major part of treatment. What you’re given for prevention depends on the stone type.
For calcium oxalate stones, the most common type, the counterintuitive advice is to eat more calcium, not less. Getting 1,200 milligrams of dietary calcium daily (from food, not supplements) reduces the amount of oxalate your body absorbs, which is what actually drives stone formation. Spreading calcium-rich foods across all three meals is more effective than getting it all at once. Your doctor may also prescribe a thiazide diuretic like hydrochlorothiazide or chlorthalidone, which reduces the amount of calcium your kidneys release into the urine.
For uric acid stones, potassium citrate works as both a treatment and long-term preventive measure by keeping urine pH in a safe range. Reducing red meat and shellfish intake also helps lower uric acid levels.
Across all stone types, the single most effective prevention strategy is drinking enough water to produce at least 2.5 liters of urine per day. That dilution alone significantly reduces the chance of crystals forming in the first place.