Passing a kidney stone can be very painful. Shock wave lithotripsy is a procedure that's not surgery. It uses high-energy shock waves to break the kidney stone into smaller pieces. This makes them easier to pass. This treatment is also called extracorporeal shock wave lithotripsy (ESWL). Lithotripsy takes about an hour. You often have it as an outpatient. It's done in a hospital, lithotripsy center, or mobile lithotripsy van. You will likely go home the same day. This treatment is not used for all types of kidney stones. Your doctor will discuss whether this is the right treatment for the type of stone you have.