Kidney pain symptoms: how it differs from back pain

Your lower back hurts, but you can't tell whether it is ordinary strain or your kidneys. Kidney pain symptoms often resemble back pain, so many people dismiss a kidney problem as “a cold in the back” or, the other way round, worry about a simple muscle strain. In this article we explain where and how kidney pain is felt, how to tell it apart from back pain, and which signs mean you should see a doctor without delay.

Where are the kidneys and where is the pain felt?

The kidneys are two bean-shaped organs on either side of the spine, beneath the lower ribs. They filter the blood, make urine and help keep the body's balance of fluid and salts.

That is why kidney pain is usually felt not at the very bottom of the back but higher up — under the ribs, at the back and side. According to the NHS, kidney stone pain often starts in the side of the abdomen or the lower back and can spread to the groin. With a kidney infection, the pain is in the lower back, the side or just under the ribs.

The pain is often on one side — right or left — because the problem usually begins in one kidney. Pain on both sides, however, does not rule out the kidneys.

What are the symptoms of kidney pain?

Kidney pain rarely comes alone — it usually comes with other symptoms. Based on NIDDK and NHS information, watch for:

Sharp, severe pain in the lower back, side, lower abdomen or groin; it comes in waves, getting stronger and then easing.
Changes in urine colour: pink, red or brown urine (blood in the urine), cloudy or foul-smelling urine.
Changes in urination: needing to pee often, pain or burning when peeing, difficulty peeing or passing only a little urine.
General symptoms: fever, chills, nausea and vomiting.

The sudden attack of pain when a stone moves into the urinary tract is called renal colic. During it, people often cannot find a comfortable position and feel restless. Small stones, on the other hand, sometimes cause no symptoms at all and pass in the urine unnoticed.

How can you tell kidney pain from back pain?

Most back pain is linked to muscle strain, lifting incorrectly, sitting for long periods or spine problems (for example osteochondrosis, a slipped disc or a trapped nerve). The NHS notes that back pain is very common and usually improves within a few weeks. The table shows the main differences:

Sign	Kidney pain	Back pain (muscles, spine)
Location	Under the ribs, at the back and side, often on one side; may spread to the groin or lower abdomen	Lower back, along the spine or in the muscles; may spread to the buttock and leg
Character	Comes in waves or attacks, sometimes unbearable	Often dull, aching or shooting with movement
Link to movement	Usually barely changes with position	Worse when bending, twisting or lifting; eases with rest
Urine	Colour or smell may change; blood in urine, pain when peeing	Usually unchanged
Fever	Fever and chills with infection	Usually none
Other signs	Nausea, vomiting, weakness	Numbness or shooting pain in the leg (trapped nerve)

This table is only a guide. Checking yourself is not a diagnosis: kidney and spine problems can occur at the same time, and the symptoms sometimes look very alike. Some people tap their back with the edge of the hand — doctors use this during an examination, but at home it gives no reliable answer.

If your pain depends mainly on movement and posture, also read our article on the main causes of lower back discomfort.

What causes kidney pain?

Kidney stones and “sand”

According to the NIDDK, stones form when urine contains high levels of calcium, oxalate and phosphorus. When a stone or gravel enters the urinary tract and blocks it, severe pain develops. The NHS notes that a diet high in protein and low in fibre, inactivity, frequent urinary infections, a close relative with kidney stones and a previous stone all make another stone more likely. Learn more in our kidney stones guide.

Kidney infection (pyelonephritis)

This is a bacterial infection that usually starts in the bladder and travels up to one or both kidneys (NIDDK). The main signs are fever, pain in the back or side and pain when peeing. The NHS adds nausea, diarrhoea, aching muscles, flu-like symptoms, needing to pee often and urgently, and dark or cloudy urine. Early treatment prevents most complications, so do not wait it out.

Other causes

Less common causes — kidney cysts, other blockages to urine flow or injuries — can only be identified by a doctor through tests. Also, pain that feels like kidney pain can actually come from the bowel, the gynaecological organs or the spine.

What should you do when your kidneys hurt?

Track your symptoms: where the pain is, how strong it is and whether it comes in waves; take your temperature and look at your urine colour. Your doctor will need this information.
Fluids: unless a doctor has restricted your fluids, drink enough water. With heart or kidney failure, your doctor decides how much to drink.
Do not prescribe yourself antibiotics: confirming an infection and choosing a medicine is the doctor's job.
Take painkillers after checking with a doctor or pharmacist — especially if you have kidney disease or a stomach ulcer, or take other medicines.
Do not lose time on folk remedies: trying to “flush out” a stone with large amounts of infusions of unknown composition means that, if the urinary tract is blocked or infected, you see a doctor too late.

To the popular question “how to pass a kidney stone at home”, the honest answer is: small stones sometimes pass on their own, but only tests can show a stone's size, position and type. Large stones and severe pain are a job for a urologist.

How does a doctor check you?

A GP or urologist will ask about your symptoms, examine you and order the tests you need:

a urine test — to look for blood and signs of infection;
a blood test — signs of inflammation and markers of kidney function (for example creatinine);
an ultrasound scan of the kidneys and urinary tract;
if needed, a CT scan.

If a stone passes on its own, keep it and take it to your doctor: knowing the stone type helps shape later diet advice.

When to see a doctor

If you have any of the following, do not wait — see a doctor the same day or call an ambulance (103 in Uzbekistan):

back or side pain together with fever, chills or feeling generally very unwell;
blood in the urine — pink, red or brown urine;
being unable to pee, or passing almost no urine all day;
unbearable pain coming in attacks (renal colic), especially with vomiting;
a temperature below 36 °C or repeated vomiting;
confusion, severe drowsiness or difficulty speaking — this needs emergency help;
any kidney or urinary symptoms during pregnancy;
back pain with numbness or weakness in both legs, loss of feeling around the genitals or bottom, or losing control of urine or stools — this may be a spinal emergency (NHS).

If back pain does not improve within a few weeks, gets worse at night, does not ease with rest or comes with unexplained weight loss, book a routine appointment with your doctor.

Everyday habits for kidney health

There is no need to “cleanse” your kidneys — healthy kidneys do their job on their own. What helps them most is simple: drinking enough water (your urine should be pale), cutting down on salt, a healthy weight, staying active and taking prescribed medicines on time. Which foods and drinks help and why herbal teas do not suit everyone is covered in detail in our article on foods and herbal teas good for the kidneys.

Remember: no supplement replaces a balanced diet, enough sleep, physical activity and medicines prescribed by your doctor.

How Nutva Nefro can help

Nutva Nefro is a biologically active dietary supplement made by NUTVA PHARM LLC (Uzbekistan). It supports the normal function of the kidneys and urinary system and the body's fluid balance. Each capsule (500 mg, 60 capsules per pack) contains:

Phyllanthus niruri — 50 mg;
Orthosiphon stamineus (Java tea, “kidney tea”) — 20 mg;
magnesium citrate — 120 mg;
field horsetail (Equisetum arvense) — 20 mg;
potassium citrate — 150 mg;
madder (Rubia tinctorum) — 40 mg;
rosemary — 20 mg;
Aerva lanata — 20 mg;
vitamin B6 — 20 mg.

Permit No. 1594424. The product is not a medicine and does not replace treatment for kidney stones or infection prescribed by a doctor. If you have kidney failure, heart disease or high blood potassium, consult a doctor first. Large stones and severe pain are treated only by a urologist. During pregnancy — only after consulting your doctor. How to take it — follow the instructions on the pack and your doctor's advice.

Frequently asked questions

Where is kidney pain felt — on the right or the left?

Kidney pain is usually felt under the lower ribs, at the back and side, and often on one side — right or left. As a stone moves down the ureter, the pain can spread to the lower abdomen and groin. The side of the pain alone is not enough for a diagnosis.

What can I do at home when my kidneys hurt?

Take your temperature, watch your urine colour and, unless a doctor has restricted fluids, drink enough water. Do not prescribe yourself antibiotics and do not lose time on unknown herbal infusions. With fever, blood in the urine or severe pain, see a doctor straight away.

Is my back pain from the kidneys or the spine — how can I tell?

Muscle and spine pain usually gets worse when bending, twisting or lifting and eases with rest. Kidney pain often does not depend on position and may come with urine changes, fever or nausea. A urine test and an ultrasound give the definite answer.

Which tests should I have for kidney symptoms?

Usually a urine test, a blood test (including kidney function markers) and a kidney ultrasound are ordered. If needed, the doctor will recommend a CT scan. Your doctor decides which tests you need based on your symptoms.

Can you pass a kidney stone at home?

Small stones sometimes pass in the urine on their own, but only tests show a stone's size and position. A large stone can block the urinary tract and lead to infection, so experimenting at home is risky. Large stones and severe pain are treated only by a urologist.

What are the symptoms of a kidney infection (pyelonephritis)?

The main signs are fever, chills, pain in the back or side and pain when peeing. Nausea, needing to pee often, and cloudy or dark urine are also possible. This needs a doctor's examination: early treatment helps prevent complications.