Only one common type of kidney stone can actually be dissolved with medication: uric acid stones. These make up about 10% of all kidney stones. The most common type, calcium oxalate, cannot be dissolved once formed and must either pass on its own or be removed through a procedure. Knowing what kind of stone you have is the essential first step, because it determines whether dissolution is even possible.
Why Stone Type Determines Your Options
Kidney stones form from different minerals, and each type responds differently to treatment. Uric acid stones are the only type that has shown consistent success with oral dissolution therapy. They form in acidic urine and can be broken down by making urine more alkaline. Calcium oxalate stones, which account for roughly 70-80% of all kidney stones, are chemically stable inside the body and resist dissolution. No proven method exists to dissolve them in a living person. Struvite and cystine stones each have their own treatment paths, but true chemical dissolution is largely limited to uric acid.
A CT scan can offer clues about stone composition. Uric acid stones tend to appear less dense than calcium stones on imaging, but the overlap in density readings between stone types means a CT scan alone isn’t always reliable for identification. Your doctor may also use urine tests, blood work, and your medical history (particularly a history of gout) to determine whether your stone is likely uric acid.
How Uric Acid Stones Are Dissolved
Uric acid stones dissolve when urine pH rises into the range of 6.5 to 7.0. At that level, the chemical environment becomes unfavorable for uric acid crystals, and the stone gradually breaks apart. The primary medication used to achieve this is potassium citrate, an oral alkalinizing agent that raises urine pH over time. If you also have elevated uric acid levels in your blood or urine, or a history of gout, a medication that lowers uric acid production is often added alongside potassium citrate.
For people with kidney disease or those who can’t tolerate potassium citrate, sodium bicarbonate serves as an alternative. The goal is the same: shift the urine from acidic to mildly alkaline and hold it there long enough for the stone to dissolve.
Dissolution isn’t instant. You’ll need to take medication consistently, often for weeks to months, depending on the stone’s size. During this time, you’ll likely monitor your urine pH at home using test strips and have follow-up imaging to track progress. Staying in the target pH range is critical. If your urine drifts back toward acidic, the stone can stop shrinking or even grow.
What About Cystine Stones?
Cystine stones form in people with a genetic condition called cystinuria, which causes the kidneys to excrete too much of an amino acid called cystine. These stones can be partially managed with medications that react with cystine to form a more soluble compound that the kidneys can flush out more easily. Tiopronin is the most commonly used drug for this purpose, with D-penicillamine as an older alternative that tends to have more side effects. Raising urine pH and drinking large amounts of fluid are also part of managing cystine stones, but full chemical dissolution is harder to achieve than with uric acid stones.
Calcium Oxalate Stones Can’t Be Dissolved
If you have a calcium oxalate stone, which is the most common type, there is currently no medication or home remedy that will dissolve it inside your body. Laboratory research has explored compounds like sodium tripolyphosphate, which dissolved over 90% of calcium oxalate crystals in water and about 63% of human kidney stone material in artificial urine. But these are early-stage experiments in test tubes, not treatments available to patients. The chemistry that works in a lab dish doesn’t translate directly to the complex environment inside a kidney.
Small calcium stones (under about 5-6 mm) often pass on their own with increased fluid intake and pain management. Larger stones may require procedures like shock wave lithotripsy, which uses sound waves to fragment the stone, or ureteroscopy, where a thin scope is threaded up to the stone and it’s broken apart with a laser. These aren’t dissolution in the chemical sense, but they are how most calcium stones are dealt with.
The Role of Fluids
Regardless of stone type, high fluid intake is a cornerstone of both treatment and prevention. The NHS recommends drinking up to 3 liters of fluid per day to keep urine dilute. The goal is urine that stays clear or very pale yellow throughout the day. Concentrated urine allows minerals to crystallize more easily, so simply drinking more water can slow stone growth and help smaller stones move through the urinary tract.
Water is the best choice. Spacing your intake throughout the day matters more than drinking large amounts at once, and drinking a glass before bed helps prevent overnight concentration of urine.
Do Lemon Juice and Home Remedies Work?
Lemon juice and lemonade are widely promoted as natural alternatives to potassium citrate because citrus fruits contain citrate, which inhibits stone formation. The idea has some basis in science, but the reality is more complicated than the headlines suggest.
Citrus juices do contain citrate and can have a mild alkalinizing effect on urine. Orange juice, for instance, has been shown to raise urinary citrate levels more effectively than lemonade. But in at least one study, lemonade failed to increase urinary citrate or pH levels at all. And orange juice comes with a downside: it also increases urinary oxalate and doesn’t reduce calcium excretion the way potassium citrate does. That means orange juice doesn’t lower the risk of calcium oxalate stone formation as effectively as the medication it’s being compared to.
Citrus juice consumption gained popularity partly because potassium citrate can be hard to stick with as a long-term treatment. Drinking juice feels easier and more natural. But if you’re trying to dissolve an existing uric acid stone, relying on lemon juice alone is unlikely to raise your urine pH reliably enough to get the job done. It’s better understood as a supplementary habit or a mild preventive measure, not a replacement for prescribed dissolution therapy.
Other commonly mentioned remedies, like apple cider vinegar or herbal supplements, lack strong clinical evidence for dissolving any type of kidney stone.
Preventing New Stones From Forming
Once you’ve dealt with a stone, prevention becomes the priority, since recurrence rates are high. The basics apply to nearly all stone types: drink enough fluid to produce at least 2.5 liters of urine per day, reduce sodium intake (high salt increases calcium in urine), and eat moderate amounts of animal protein, which can raise uric acid levels and lower urine pH. For calcium stone formers, getting enough dietary calcium from food (not supplements) actually helps by binding oxalate in the gut before it reaches the kidneys.
If you’ve had a uric acid stone and achieved dissolution, staying on a maintenance dose of potassium citrate can prevent recurrence by keeping urine pH in a safe range. For recurrent calcium oxalate stones, potassium citrate is also used preventively, not to dissolve existing stones, but to raise citrate levels in urine, which interferes with crystal formation.