Sodium bicarbonate does not dissolve urinary stones. Sodium bicarbonate can raise the pH of the urine, but it does not dissolve or reduce the size of stones that have formed. Interventional energy such as extracorporeal shock wave lithotripsy, laser or pneumatic ballistics is needed to break up the stones and remove them from the body. Raising the pH of the urine helps to inhibit stone formation by taking sodium bicarbonate or sodium potassium bicarbonate pellets. Citrate is an effective ion in the urinary system to prevent stone formation, and can raise the pH of the urine to prevent stone formation, but it cannot dissolve stones that have already formed. With the exception of uric acid stones, urinary stones may decrease in size or dissolve when uric acid is lowered or when medications are taken to suppress uric acid. Other types of stones do not dissolve and require treatment such as extracorporeal shock wave lithotripsy or surgery to remove the stones that have formed.