Kidney stones, also called urinary stones, are rock-like substances in one or both of your kidneys. They form when you have an imbalance of minerals, like calcium or uric acid, in your urine (pee). Kidney stones can be as small as a grain of sand or as large as a a golf ball, although they rarely get that big. The size of a green pea is more common.
It's important to treat kidney stones so they don't cause serious health issues like UTIs (urinary tract infections), kidney infections, or loss of your kidney function.
So how do you know if you have kidney stones? Here are some of the signs to look out for.
Pain in Your Sides
Very small kidney stones might not cause any symptoms. They can pass out of your kidneys to your bladder and you may pee them out without even realizing it.
But if have a larger stone that gets stuck in one of your ureters, the tubes that connect each of your kidneys to your bladder, you'll feel it. One of the most common signs of a kidney stone is intense, shooting pain. Another term for this is renal colic. It happens when pee that can't move past the stone starts backing up into your kidney and pressing on its sensitive nerves.
Your kidneys sit on either side of your middle back. If you have a kidney stone, you'll have what doctors call "flank pain," which is pain in your side, somewhere between your ribs and hip. It will likely will come in waves, getting really intense then stopping for a while. This is due to whether or not pee is able to move around the stuck stone. It may be so severe that it makes you sick to your stomach or throw up.
Radiating Pain
Kidney stone pain often spreads from your sides to your abdomen (belly). Some people describe their pain as a stomachache that won't go away. You could also feel pain in your groin (the area between your hip and thigh.) If you're a man or were assigned male at birth, you could even feel it in your testicles. Rarely, a kidney stone can also cause lower or middle back pain.
Painful Urination
Trying to pee when you have a kidney stone can cause a burning or stinging feeling. The medical term for this is dysuria. It can actually happen for a lot of different reasons, like using a perfumed soap, a vaginal yeast infection, a UTI, or an STI (sexually transmitted infection) like chlamydia or gonorrhea. You won't know the cause for sure until you see your doctor.
Constant Urge to Pee
Once a stone moves out of your kidney, it can move down your ureter towards your bladder. The pressure that it puts on your bladder can make you feel like you need to pee a lot more than usual. For most people, peeing more than eight times a day or twice during the night is a sign you need to speak to your doctor.
Hematuria
Blood in your pee, which doctors call hematuria, may be your only kidney stone symptom. It can make your pee look red, pink, or brown. But everyone is different. You could also have traces of blood that are easy to miss without a lab test.
Hematuria happens when your kidney's filters, or other parts of your urinary tract, stop working like they're supposed to. As a result, red blood cells sneak into your pee.
Cloudy Urine
Healthy pee should look light yellow and clear. This means you're getting enough fluids and your body is getting rid of waste the way it should. Your pee can become foggy for a lot of reasons, ranging from not drinking enough fluids to eating a lot of fruits and vegetables without a lot of meats, cheeses, and grains.
But hazy pee can sometimes also signal that your kidneys are working harder than usual to flush out a high amount of minerals and salts, which stick together to form kidney stones.
Smelly Urine
It's easy to forget that pee isn't just excess fluid from your body. It's also filled with waste from your kidneys. If it contains a lot of waste, like from the chemicals that make up kidney stones, it can smell much stronger than usual. Some people with kidney stones notice that their pee smells a lot like ammonia.
Low Urine Output
Depending on the size of your kidney stone and where it is, you may find it hard to pee. It could be blocking your urinary tract.
Other Kidney Stone Symptoms
Some other signs that you have a kidney stone include:
Fever and chills. These can signal an infection in your urinary tract as a result of the stone.
Repeated infections. If you have a UTI or bladder infection that keeps clearing up and coming back, even after being treated with antibiotics, you might have a kidney stone. The bacteria that causes these types of infections can get inside the stone, where antibiotics can't treat it.
Feeling sick to your stomach. Your kidneys and gastrointestinal tract share some of the same nerves.
Tests to Know If You Have Kidney Stones
The only way to know for sure that you have a kidney stone is to see a doctor. Make an appointment if you:
- Can’t get comfortable standing, sitting, or lying down
- Have nausea and serious pain in your belly
- Notice blood in your urine
- Have a hard time trying to pee
Be ready to describe your symptoms, including when they started. Before your visit, you might want to write them down, along with a list of the medications you take. Don't forget to include over-the-counter vitamins and supplements you use. You can also try to keep track of how much you drink and pee in a 24-hour period.
If your doctor thinks you might have kidney stones, they'll likely order one or more tests.
Blood tests. These can help find out whether you have too much of certain substances in your blood, such as uric acid or calcium, that can cause stones to form.
Urine tests. These can detect stone-forming minerals in your pee or find out if you lack substances that prevent them from forming. Your doctor may advise you to collect a urine sample over the course of a day or two.
Imaging tests for kidney stones
Imaging procedures can help spot how many kidney stones you have, their size, and where in your body they are. These tests, which are painless and can be done quickly, include:
X-rays. Although very small stones might be missed on an X-ray of your abdomen, larger ones will show up.
CT scans. A more in-depth type of scan is called computed tomography, or CT scan. It uses computer technology to create a more detailed type of X-ray. A CT scanner takes pictures from several angles. A computer then puts all the images, called “slices,” together to provide a more detailed look than a standard X-ray can provide. At times, a special, safe dye called a contrast is injected in your vein to make the images inside your body easier to see. But usually, that's not needed to look at your urinary tract.
Ultrasound. This test uses sound waves, not radiation, to create pictures of your insides. A small, smooth device called a transducer is rolled across your abdomen. The low-power sound waves it makes bounce off your tissues and organs. A computer then creates images from these echoes.
Usually, you don’t need to do anything to prepare for an imaging test. But your doctor may ask you to drink a lot of water and not go to the bathroom right before a kidney ultrasound. When your bladder's full, it's easier to see on ultrasound images.
Other kidney stone tests
If other people in your family get kidney stones or you first got them as a child or teen, your doctor may suggest a genetic test. This can help ID any conditions that run in your family that may be causing your kidney stones.
Are You at Risk for Developing Kidney Stones?
Many things can raise your risk for kidney stones, including:
- Not drinking enough water
- Carrying excess weight
- Having a family member with kidney stones
- Working outside in high heat
- Holding your pee and not going when you need to
- A diet high in salt, sugar, or protein
- Digestive issues
- Bowel inflammation
- Gout
- Frequent UTIs
- Kidney disease
- Gastric bypass surgery
- Taking certain medications for a long time (including calcium-based antacids and diuretics)
Men and people assigned male at birth are more likely to get kidney stones. And once you've had kidney stones, you're also more likely to get them again.
After Your Diagnosis
How your kidney stone is treated depends on many factors, including how many you have, their size, where they are, and the amount of pain you're in.
If the stone is small and your pain isn’t severe, your doctor may take a wait-and-see approach. They could tell you to drink a lot of fluids to help flush out the stone with your pee. Over-the-counter pain relief can help manage any discomfort. You could also be prescribed a medication called tamsulosin (Flomax) for kidney stones. A type of drug called an alpha-blocker, it relaxes your ureter so it's easier to pass the stone.
Passing stones doesn't often happen overnight. It can take a few weeks to several months.
Stones that are too large to pass or risk causing other health issues can be treated a few different ways, including:
Lithotripsy. Shock waves can be used to break up the kidney stone into small pieces. This treatment usually takes about an hour, and you'll be given anesthesia that allows you to sleep through it. It's often a same-day procedure, so you won't have to stay overnight in a hospital.
Surgery. For instance, your doctor could remove small stones through a thin tube that's placed in your kidney or bladder. They can also use special surgical tools, including lasers, to break up bigger stones. Depending on the procedure that's done, you may need to go into the hospital for a few days.
Once the stone or stone fragments are out of your body, your doctor may want to send them to a lab. You may be told how to collect them in a special strainer if you pee them out. There are different types of kidney stones. Knowing which kind you have could help your doctor figure out a way to prevent more from forming.
How to prevent kidney stones
A few simple changes to your daily routine can also reduce your risk of getting more kidney stones. For instance, try to:
Drink plenty of water. Aim for at least eight to 10 8-ounce glasses each day.
Cut back on sodium. Read labels of packaged foods. Most people are advised to have no more than 2,300 milligrams of sodium each day.
Make more meatless meals. A diet high in meat, eggs, and seafood makes kidney stones more likely.
Takeaways
Kidney stones aren't life-threatening, but they can be intensely painful and lead to other health issues. See a doctor right away if you think you have one. Your doctor can do tests to figure out the next best steps to take and help you prevent new stones from forming.
