Most urologists send people home after lithotripsy with the same instruction, drink 2 to 3 liters of water a day, and that one number does two different jobs. For the next week or two it keeps urine moving fast enough to carry the stone fragments out. After that it becomes the main thing standing between you and the next stone, and that second job is the one most people quietly drop once the pain fades.
Table Of Contents
−- The short answer
- What lithotripsy actually leaves behind
- How much to drink in the first two weeks
- Signs that need a call, not more water
- The long term target is measured in urine, not glasses
- What to drink, and what the evidence says about each
- Salt, softened water, and hard water
- Activity, pain, and medicine in the first days
- What we recommend
Below is what the first few weeks actually look like, the long term urine target the American Urological Association sets, which drinks help and which work against you, and the one plumbing detail that matters if your house runs a water softener. Your urologist’s written instructions for your specific procedure come first; this fills in the reasons behind them.
The short answer
Here is the whole article in four lines, with the detail and sources further down.
- First days to two weeks. About 2 to 3 liters of fluid a day, mostly plain water, spread across the day so fragments keep moving.
- For good after that. Enough fluid to pass at least 2.5 liters of urine a day, which for most adults means drinking closer to 3 liters.
- Normal afterward. Pink or blood tinged urine for a day or two, a burning feeling as grit passes, and a bruise or dull ache over the treated side.
- Call your urologist. Fever above the line on your discharge sheet (usually 38 to 38.5 degrees Celsius, 100.4 to 101.3 degrees Fahrenheit), chills, trouble passing urine, large clots, pain your medicine does not touch, or vomiting that will not stop.
What lithotripsy actually leaves behind
Lithotripsy does not remove a stone. It breaks one. Extracorporeal shock wave lithotripsy (ESWL) aims focused shock waves through the skin at the stone, while laser lithotripsy reaches it from the inside, through a thin scope passed up the ureter (ureteroscopy), and sometimes leaves a temporary stent in place. Both send you home with gravel that still has to travel down the ureter and out through the bladder.
That trip takes a while. The Royal Berkshire NHS Foundation Trust’s ESWL aftercare leaflet warns that fragments can keep moving for up to a couple of weeks, books an abdominal x-ray before a follow up visit roughly three months out, and notes that patients usually have up to three treatments spaced at least six weeks apart. So the window after lithotripsy is not one evening. It is a few weeks of active passage, followed by years of prevention.
How much to drink in the first two weeks
The number on most discharge sheets is 2 to 3 liters of water a day. Royal Berkshire’s leaflet uses that exact range to help flush out fragments, and Nova Scotia Health’s ESWL pamphlet simply says to drink plenty of fluids for several days. No study suggests that forcing far past 3 liters clears gravel faster. A liter gulped at once mostly lands in the bladder within the hour, so steady sipping through the day does more.
Color is the easiest gauge. The University of Michigan urology department’s fluid guide puts it plainly: light yellow or clear urine means you are drinking enough. Dark yellow by midday means you are behind.
Blood in the urine is expected at first. Royal Berkshire tells patients that some blood for one to two days is normal, and to contact the urology team if it lasts longer than a week or large clots appear. People who had laser treatment with a stent often see some blood and urgency for as long as the stent stays in, and the urologist will say when it comes out.
Most clinics also ask you to strain your urine for a few days, through the strainer they hand you or a coffee filter. Nova Scotia Health asks for 3 to 4 days. Do it. The lab result on a single fragment decides which of the prevention steps below apply to you.
Signs that need a call, not more water
Extra water will not fix an infection or a blocked ureter. Contact your urologist, or go to an emergency department if you cannot reach them, for any of these.
- A fever over the threshold on your discharge sheet. Nova Scotia Health sets it at 38.5 degrees Celsius (101.3 degrees Fahrenheit); other clinics use 38 degrees Celsius (100.4 degrees Fahrenheit).
- Chills or shivering, or a general unwell feeling, which Royal Berkshire flags as a possible sign of serious infection.
- Little or no urine despite drinking normally.
- Large blood clots in the urine.
- Pain the medicine you were given does not control.
- Nausea and vomiting that will not stop, which also means you cannot keep fluids down.
A fever on top of a blocked kidney can turn serious within hours. That one does not wait for morning.
The long term target is measured in urine, not glasses
Once the fragments clear, the goal changes. The American Urological Association’s medical management guideline tells clinicians to recommend a fluid intake that produces at least 2.5 liters of urine a day for every stone former, and the 2026 update repeats the target, 2.5 liters or 85 ounces of urine daily, preferably from water, for adults with calcium based stones. The word that matters is urine. You also lose water through breath and skin, so most adults need to drink about 3 liters to pass 2.5.
The evidence behind that number is old but solid. In a five year randomized trial published in the Journal of Urology in 1996 (Borghi and colleagues), 199 people with a first calcium stone were split into a high water intake group and an untreated group. Twelve of 99 in the water group formed another stone, against 27 of 100 in the untreated group, and the average time to a recurrence stretched from about 25 months to about 39.
The hard part is keeping it up. The PUSH trial, published in The Lancet in March 2026, gave 1,658 stone formers Bluetooth smart bottles, personal fluid prescriptions, text reminders, coaching, and cash incentives. Urine volume went up. Not by enough. After two years, symptomatic recurrence was 19 percent in the intervention group and 20 percent with usual care (hazard ratio 0.96), and the investigators were careful to say this does not mean fluid fails, only that hitting the volume every day is harder than anyone expected.
So make the target something you can see. A standard 10 cup filter pitcher holds about 2.4 liters. Fill it every morning, empty it by evening, and count coffee and meal drinks on top of it. If your tap water tastes of chlorine, filtering it also removes the most common excuse for drifting to soda, and our comparison of the best water filter pitchers lists which models carry NSF/ANSI 42 certification for chlorine taste and which add health claims such as lead reduction under Standard 53.
What to drink, and what the evidence says about each
Plain water is the drink the guideline names, and the University of Michigan fluid guide calls it the least expensive and very effective. Other drinks either add a small edge for specific stone types or work against you.
Lemon juice, at a dose that actually counts
Lemon helps for a specific reason. Citrate binds calcium in urine and slows calcium stone crystals from forming, but a squeeze in a glass delivers very little. The protocol studied at Duke, as described by the University of British Columbia’s stone centre, mixes 120 milliliters (about half a cup) of reconstituted lemon or lime juice into 2 liters of water over the day. That gives about 5.9 grams of citric acid, more than five times what orange juice or bottled lemonade provides.
In a retrospective Duke review reported by Urology Times, 12 patients on that lemonade raised urinary citrate by an average of 354 milligrams a day, against 472 milligrams for 15 matched patients on potassium citrate pills, and stone formation fell from about one stone per patient per year to 0.13. Small numbers, no randomization. It matters most when a 24 hour urine test shows low citrate. Sweeten it with a sugar free sweetener or not at all.
Coffee, tea, and orange juice
These look better than their reputation. A 2013 analysis in the Clinical Journal of the American Society of Nephrology (Ferraro and colleagues) followed 194,095 people in three cohorts for a median of more than eight years and found coffee, tea, and orange juice linked to a lower risk of stones.
Soda and cranberry juice
The same analysis found that one or more sugar sweetened colas a day carried a 23 percent higher risk than less than one a week, and sugary non cola drinks such as punch showed the same pattern. The AUA’s 2026 update says adults with stones may be advised to limit soft drinks. The sugar in a can of soda costs you in other ways too. Cranberry juice is the other surprise, since the University of Michigan guide notes it has been found to raise the risk of calcium oxalate and uric acid stones.
Apple cider vinegar, celery, basil, and pomegranate
The evidence for these stops at lab dishes and rats. No human trial shows any of them dissolving or preventing kidney stones. Apple cider vinegar has a real downside, because its acid can wear tooth enamel and aggravate acid reflux, so if you try it anyway, dilute it heavily and do not count it toward your water.
Salt, softened water, and hard water
This is where your plumbing actually touches stone risk, though not in the way most people assume.
Sodium from an ion exchange softener
The AUA guideline tells people with calcium stones and high urinary calcium to limit sodium, because the kidneys dump calcium into urine along with the sodium they excrete. A salt based softener swaps calcium for sodium. University of Nebraska Extension puts the added sodium at about 8 milligrams per liter for every grain per gallon of hardness removed, and University of Maryland Extension gives an average softened water figure of 278 milligrams per liter. At 3 liters a day that is roughly 830 milligrams of sodium from water alone, more than a third of the 2,300 milligram daily ceiling.
Extra water will not flush salt out any faster, so the fix is the sodium going in. Run an unsoftened cold line to the kitchen tap, or drink from an under sink reverse osmosis unit, which strips sodium along with other dissolved solids.
Hard water is not the cause
Many people assume the calcium in hard water feeds kidney stones. The largest look at the question, a UK Biobank cohort of 288,041 people published in the International Journal of Surgery in 2024 (Zhang and colleagues), found no significant link between water hardness or calcium and new stones across the whole population. Magnesium above 5 milligrams per liter was tied to a 12 percent lower risk (hazard ratio 0.88). Only in women and people over 60 did hard water and calcium show an 18 to 34 percent higher risk.
That lines up with the AUA’s advice to keep eating a normal 1,000 to 1,200 milligrams of dietary calcium rather than cutting it. If you want to understand what makes water hard in your area, a test is cheap, but a softener is not a kidney stone treatment.
Activity, pain, and medicine in the first days
Light walking is fine and may help fragments move. Nova Scotia Health says you can return to normal activity once your urine is clear of blood, and many clinics ask you to skip hard exercise and work for the first 24 hours. For mild pain the same pamphlet names acetaminophen, and a warm bath can ease a sore back. Do not drive within 24 hours of a prescription pain reliever, and finish any antibiotic course you were given.
What we recommend
Treat the 2 to 3 liters on your discharge sheet as a permanent habit rather than a two week prescription, and measure it with a full pitcher you empty every day instead of a mental tally. Then get the strained fragment analyzed, because that one lab result tells you whether lemon juice, a lower sodium tap, or a prescription is worth adding on top of the water.
Jay
Jay is a health and wellness enthusiast with expertise in water quality and nutrition. As a knowledgeable advocate for holistic well-being, Jay successfully manages Type 2 Diabetes through informed lifestyle choices. Committed to sharing reliable and authoritative insights, Jay combines firsthand experience with a passion for enhancing health."