How Long Does It Take to Pass a Kidney Stone?

How a Kidney Stone Actually Passes

Kidney stones form when minerals like calcium, oxalate, and uric acid build up in your urine and crystallize. They can sit quietly inside your kidney for years without causing any symptoms.

The pain starts when a stone shifts and drops into the ureter, which is the narrow tube connecting your kidney to your bladder. Your body responds by contracting that tube to push the stone downward. Those waves of intense cramping are your body doing exactly what it is supposed to do. It just does not feel that way in the moment.

What the Timeline Looks Like

Stone size is the biggest factor in how long the process takes and whether you will need medical help at all.

Stones smaller than 4mm

These pass on their own about 80 percent of the time. On average, they take around 31 days to clear your urinary tract. Many people manage this size with hydration and over-the-counter pain relief at home.

Stones between 4mm and 6mm

About 60 percent of stones in this range pass naturally, but it tends to take longer, up to 45 days on average. Some people in this category benefit from a prescription medication to help relax the ureter and move things along faster.

Stones larger than 6mm

Only about 20 percent of these pass without medical help. For the ones that do pass on their own, it can take several months or longer. Most stones this size require a procedure to break them up or remove them safely. A urologist will generally allow up to six weeks for natural passage before recommending intervention.

Where the stone is located also matters. A stone sitting in the lower ureter, close to the bladder, has a much better chance of passing on its own than one stuck near the kidney.

How to Pass Kidney Stones: What You Can Do at Home

If your stone is small and your doctor has confirmed it is safe to wait, there are a few things that you can do to help you pass it at home.

The most important step is to drink more water than you think you need. Aiming for two to three liters per day helps increase urine flow, which creates more force to move the stone through the urinary tract. Many doctors also recommend adding citrus juices like lemon water, since they contain citrate, a compound that can help prevent the stone from growing larger while you wait for it to pass. Sometimes your physician can prescribe medications to also aid in stone passage.

Staying physically active can also make a difference. Gentle walking helps shift a stone along the urinary tract, and you do not need to do anything strenuous; a short daily walk is enough.

When it comes to managing pain, ibuprofen and naproxen tend to be the best options for kidney stone pain relief at home. They work by reducing swelling around the stone in the ureter, which can ease the painful spasms and slightly widen the passage. Placing a heating pad on your lower back or abdomen between doses can also help take the edge off.

Finally, it is worth cutting back on salt and processed foods while you are waiting for the stone to pass. Sodium increases the amount of calcium in your urine, which can feed stone growth. This is a good time to eat clean and stay well hydrated to give your body the best chance of moving the stone along on its own.

When Home Management Is Not Enough

Knowing how to manage kidney stone pain at home is helpful, but there are certain signs that mean you need more than rest and fluids. A fever or chills alongside pain can indicate a urinary infection, which becomes a medical emergency when a stone is involved, so you should not wait that one out. If vomiting is preventing you from staying hydrated, your body cannot do what it needs to do, and you may need IV fluids. Pain that does not respond to over-the-counter medication is another sign that it is time to call your doctor. If you have not seen any progress after four to six weeks, it is time to explore other options.

When medical treatment is needed, there are effective, minimally invasive options available. Extracorporeal Shock Wave Lithotripsy, also known as ESWL, uses sound waves to break a larger stone into smaller pieces that can then pass naturally. Ureteroscopy with laser lithotripsy removes the stone directly through a small scope, with most patients back to normal activity within a week. Your urologist may also prescribe alpha-blockers like tamsulosin, which relax the muscles of the ureter and can cut the time it takes to pass a stone by several days.

When to See a Urologist

You do not have to be in a full-blown crisis to reach out. If you are not sure whether your stone will pass on its own, if your pain is getting worse instead of better, or if this is not your first time dealing with kidney stones, a urologist can help you figure out the right plan.

At Advanced Urology, our board-certified urologists specialize in kidney stone diagnosis and treatment across both men's and women's health. We can determine the size and location of your stone, recommend the most appropriate next step, and get you comfortable as quickly as possible. With multiple locations across the Atlanta area, getting answers is easier than you might think.

Schedule an appointment today to talk with a specialist who can help you get through this.