Only one type of kidney stone, uric acid stones, can be reliably dissolved with medication. Other stone types, like the more common calcium oxalate stones, generally need to pass on their own or be removed through a procedure. That said, several strategies can help stones move faster, slow their growth, and lower your chances of forming new ones.
Why Most Kidney Stones Can’t Be Dissolved
About 80% of kidney stones are made of calcium oxalate or calcium phosphate. These minerals form hard crystals that don’t break down in response to changes in urine chemistry. No pill, drink, or home remedy can dissolve a calcium-based stone once it has formed. If you have one, the path forward is either passing it naturally (for smaller stones) or a procedure to break it up or remove it.
Uric acid stones make up roughly 5% to 10% of all kidney stones, and they’re the exception. They form in acidic urine and dissolve when the urine becomes more alkaline. This makes them uniquely treatable with oral medications.
How Uric Acid Stones Are Dissolved
The goal of uric acid stone dissolution is straightforward: raise the pH of your urine from acidic (below 5.5) to a target range of 6.5 to 7.0. At that pH, uric acid crystals gradually break apart and dissolve back into the urine. Three medications are commonly used:
- Potassium citrate is the most widely prescribed option. It directly raises urinary pH. Doctors typically start at 20 to 30 milliequivalents per day, split across two or three doses, and adjust based on urine pH readings you do at home with test strips.
- Calcium carbonate (antacid tablets) also raises urine pH and can serve as a simpler alternative.
- Allopurinol works differently. Instead of changing urine pH, it lowers the amount of uric acid your body produces. It’s often added when blood uric acid levels are elevated.
A systematic review of dissolution therapy studies found that most protocols used potassium citrate at 20 milliequivalents three times daily, with dose adjustments guided by regular urine pH monitoring. For patients who couldn’t tolerate potassium citrate or had reduced kidney function, sodium bicarbonate was used as an alternative, starting at 2 grams three times daily and increasing as needed.
Dissolution doesn’t happen overnight. Depending on stone size, treatment typically takes weeks to several months of consistent medication and monitoring. Smaller stones dissolve faster, and success depends heavily on keeping your urine pH in the target range throughout the day, not just at one reading.
Cystine Stones: A Special Case
Cystine stones are rare, caused by a genetic condition called cystinuria. They can sometimes be managed with a combination of high fluid intake, urinary alkalinization, and specialized medications that break apart the cystine molecule into smaller, more soluble fragments. These drugs are typically reserved for cases where hydration and pH management alone aren’t enough to keep cystine levels below 300 milligrams per liter in the urine.
What Hydration Actually Does
Drinking more water won’t dissolve a stone, but it’s one of the most effective things you can do to help a small stone pass and to prevent new ones from forming. The mechanism is simple: more fluid dilutes the minerals in your urine, making it harder for crystals to form and grow. It also increases urine flow, which helps push small stones through the urinary tract.
The University of Chicago Kidney Stone Program recommends 3 to 4 liters of fluid per day under normal conditions, enough to produce 2.5 to 3 liters of urine. That’s significantly more than most people drink. A practical way to check: your urine should be pale yellow or nearly clear throughout the day. If it’s dark, you’re not drinking enough.
Lemon Juice and Natural Citrate
Citrate is a natural inhibitor of kidney stone formation. It binds to calcium in the urine, preventing it from linking up with oxalate to form crystals. People with low urinary citrate levels are at higher risk for calcium stones, which is why potassium citrate is prescribed both for dissolution (of uric acid stones) and for prevention (of calcium stones).
Lemon juice is the richest natural source of citrate among common fruits. Research cited by Harvard Health suggests that drinking half a cup of lemon juice concentrate diluted in water each day, or the juice of two lemons, can meaningfully increase urinary citrate levels and likely reduce stone risk. This isn’t a substitute for medication when you have a stone that needs treatment, but it’s a reasonable daily habit for prevention, especially if you’ve had calcium oxalate stones before.
Lemonade made with real lemons (not powdered mix) provides the same benefit. Orange juice also contains citrate, though it adds calories and sugar that lemon water doesn’t.
Apple Cider Vinegar: Limited Evidence
Apple cider vinegar is one of the most commonly searched home remedies for kidney stones. A recent lab study found that it could inhibit and even dissolve struvite crystals (a type of stone associated with urinary tract infections) in a controlled gel medium. Higher concentrations of apple cider vinegar led to greater crystal breakdown, and imaging confirmed that crystal surfaces were visibly disintegrated.
The catch: this was an in vitro study, meaning it was done in a lab dish, not in a human body. The researchers themselves noted that this technique is a screening step to identify promising substances “prior to complex biological examination.” No clinical trials have confirmed that drinking apple cider vinegar dissolves kidney stones in people. The acid concentration that reaches your kidneys after digestion, absorption, and filtration is vastly different from what was applied directly to crystals in a lab. It’s not harmful in small amounts, but treating it as a proven remedy would be getting ahead of the science.
Dietary Changes That Matter
For calcium oxalate stones (the most common kind), certain dietary shifts can slow stone growth and reduce recurrence even though they won’t dissolve existing stones:
- Reduce sodium intake. High salt consumption increases calcium in your urine. Keeping sodium below 2,300 milligrams per day makes a measurable difference.
- Moderate animal protein. Red meat, poultry, and seafood increase uric acid production and lower urinary citrate. This matters for both uric acid and calcium stones.
- Get enough dietary calcium. This sounds counterintuitive, but calcium from food binds oxalate in your gut before it reaches the kidneys. Low-calcium diets actually increase stone risk.
- Limit high-oxalate foods. Spinach, rhubarb, beets, nuts, and chocolate are particularly high in oxalate. You don’t need to eliminate them, but pairing them with calcium-rich foods helps.
When Dissolution Isn’t an Option
If you have a calcium-based stone that’s too large to pass on its own (generally larger than 5 to 6 millimeters), the main options are procedures rather than medications. Shockwave lithotripsy uses sound waves from outside the body to fragment stones into smaller pieces that can then pass naturally. Success rates are highest for stones 12 millimeters or smaller. For larger or harder stones, ureteroscopy (a thin scope threaded up through the urinary tract) or percutaneous surgery may be recommended.
Knowing your stone type is essential for choosing the right approach. If you’ve passed a stone, saving it for lab analysis tells you exactly what it’s made of. If imaging suggests a uric acid stone (they tend to be invisible on standard X-rays but visible on CT scans), your doctor can start dissolution therapy and potentially avoid a procedure entirely.