The single best position to help pass a kidney stone is lying on the side where the stone is located, with that side facing down. In one study, 88.3% of patients who slept with the stone side down were stone-free at three months, compared to 70% of those who slept with the stone side up. Gravity, increased blood flow to that kidney, and the natural anatomy of the urinary tract all work in your favor when you use positioning strategically.
Why Sleeping Stone-Side Down Works
When you lie on your side, the kidney closest to the mattress receives significantly more blood flow. Research using kidney perfusion scans found that 80% to 90% of people lying on their side had measurably increased blood flow to the lower kidney within just 30 minutes. More blood flowing through the kidney means more urine production on that side, which creates additional pressure to push the stone downward through the ureter, the narrow tube connecting your kidney to your bladder.
The numbers are compelling. Patients who slept with their stone side down were three times more likely to be stone-free than those who slept on the opposite side. So if your stone is in your right kidney or right ureter, sleep on your right side. Left stone, left side down. It’s a simple change that takes advantage of gravity and your body’s own plumbing.
Upright and Moving During the Day
When you’re awake, staying upright and walking is your best bet. The ureter runs roughly vertically when you’re standing, so gravity naturally pulls the stone toward the bladder. Light activity like walking also generates small rhythmic movements that can help nudge a stone along. Sitting still for long stretches works against you because the stone has less mechanical encouragement to move.
You don’t need to power walk or exercise intensely. Gentle, sustained movement throughout the day is more useful than short bursts of vigorous activity, especially since kidney stone pain can make anything strenuous miserable. Even pacing around your home counts.
How Gravity Affects Stone Movement
Gravity has a measurable effect on how stones travel. In laboratory models simulating the ureter, researchers found that even a small angle of incline dramatically changed how far a stone could drift backward (away from the bladder). At a flat angle, a stone could move 10 centimeters in under 8 seconds. At just a 20-degree incline, the stone barely moved beyond 1 to 2 centimeters, even after a full minute. At 40 degrees, movement dropped to less than 1 centimeter.
This research was done in the context of surgical stone treatment, but the principle applies to natural passage too: keeping your body positioned so the stone has a downhill path makes a real difference. Standing, walking, and sleeping on the affected side all tilt the odds in gravity’s favor.
Positions That Help With Pain
Kidney stone pain comes in waves as the ureter squeezes and spasms around the stone. During an intense episode, most people instinctively curl up or shift positions constantly, trying to find relief. There’s no single pain-relieving position that works for everyone, but a few approaches tend to help.
Lying on your affected side with your knees drawn slightly toward your chest can reduce tension on the ureter. Some people find that rocking gently between positions provides brief relief during spasms. A warm compress or heating pad on the flank (the area between your ribs and hip on the side of the stone) can relax the surrounding muscles and ease cramping, regardless of which position you’re in.
Staying hydrated is just as important as positioning. Drinking enough water to produce clear or light yellow urine keeps steady pressure behind the stone. Dehydration slows urine output and gives the stone less push.
Medications That Complement Positioning
For stones in the lower portion of the ureter (closest to the bladder), doctors sometimes prescribe a muscle-relaxing medication that loosens the walls of the ureter, making it easier for the stone to slide through. In studies, patients taking this medication passed their stones in an average of about 10 days, compared to nearly 14 days without it. They also needed roughly 40% less pain medication during the process.
Combining this kind of medical support with smart positioning gives you the fastest path to passing a stone at home. The medication relaxes the tube, gravity and blood flow push the stone, and hydration keeps everything moving.
What Size Stones Can You Pass at Home
Stones smaller than 5 millimeters (about the width of a pencil eraser) pass on their own the majority of the time. Stones between 5 and 10 millimeters sometimes pass, but the odds drop significantly as size increases. Stones larger than 10 millimeters rarely pass without medical intervention.
The location of the stone also matters. A stone that has already traveled to the lower ureter, near the bladder, is much more likely to pass than one still lodged near the kidney. Your doctor can tell you both the size and location from imaging, which gives you a realistic sense of whether positioning and hydration are likely to be enough.
Signs That Positioning Alone Isn’t Enough
Most kidney stones pass within a few days to a few weeks with conservative measures. But certain symptoms signal that the situation has become more serious. Fever or chills alongside stone pain can indicate an infection building behind the blockage, which requires prompt treatment. Persistent vomiting that prevents you from keeping fluids down undermines the hydration strategy and can lead to dehydration. Pain that remains severe despite over-the-counter relief, or complete inability to urinate, are also signals that the stone may need to be removed rather than waited out.
If your stone hasn’t moved after four to six weeks of conservative management, most urologists will recommend a procedure rather than continued waiting, since prolonged blockage can damage the kidney over time.