Where is kidney pain felt and what does it feel like?

Pain connected to your kidneys can vary, depending on the cause. “It’s often a dull ache on one side, fairly low in your back,” says consultant nephrologist Dr Rosie Donne. “It may spread to the front of your abdomen and radiate down to your groin. Pain linked to kidney stones is different – it can be a very sharp, severe pain in the side of your abdomen, which comes and goes.”

However, it can be hard to know whether pain is really related to the kidneys. “It may feel as though it’s in the kidney area, but pain in the lower back is common for lots of different reasons, such as arthritis or muscle strain,” says Dr Donne.

That’s why doctors may use the terms “loin pain” or “flank pain”, which describe the location of the pain without assuming it’s related to the kidneys.

This information page focuses mainly on kidney-related causes of loin pain.

Why do I feel kidney pain – and can kidneys actually feel pain?

Kidney tissue itself has limited pain receptors. “But pain can be triggered if the renal capsule (the fibrous covering around each kidney) is stretched – for example, if the kidney becomes swollen or enlarged,” says Dr Donne.

Pain can also come from a blockage or narrowing of the ureter, the tube that carries urine from your kidneys to your bladder.

What conditions can cause kidney pain?

Kidney pain has a range of causes, including:

• Kidney stones, which can cause a blockage in the ureter. When urine can’t flow properly into the bladder, it can build up in the ureter, which tries to push urine past the blockage with muscular spasms.
• Kidney infection – this can occur when bacteria travel from the bladder into the kidney, causing pain and other symptoms including fever, chills, aching muscles, and needing to pass urine more often and more urgently than usual.
• Polycystic kidney disease (PKD), an inherited condition that can cause the renal capsule to stretch as fluid-filled cysts enlarge the kidneys.
• Injury or trauma to the kidney area – for example, from contact sports or a fall.
• Loin pain haematuria syndrome (LPHS) – a very rare condition that usually affects young adults, causing severe loin pain, along with blood in the urine. The cause isn’t known and treatment aims to manage symptoms.

Is kidney pain a symptom of kidney stones?

Yes, kidney stones are one of the best-known causes of kidney pain. The pain may:

• be sudden and severe
• come in waves (caused by the spasms in the ureter)
• be accompanied by other symptoms, such as nausea, vomiting and blood in the urine

Is kidney pain a symptom of a kidney infection?

Yes – infection is one of the most common causes of kidney pain. Other symptoms include:

• fever and chills
• feeling or being sick
• a high temperature
• aching muscles
• passing urine more often and urgently than usual
• pain when you pass urine
• dark or cloudy urine

Does kidney pain mean my kidney disease is getting worse?

Not necessarily. “Although pain is common in people with chronic kidney disease (CKD), it isn’t usually connected to worsening kidney function,” says Rosie. “It may be caused by another condition common in people living with CKD, such as arthritis, or by a different kidney problem, like stones or an infection.”

It’s understandable to feel concerned if you notice pain – but on its own, pain isn’t a reliable sign of how your kidneys are functioning. “Tracking measures such as your eGFR and blood pressure gives a clearer picture of how your kidneys are working, and can help you feel more confident about managing your CKD,” says Rosie.

Download our booklet on understanding your test results and speak to your healthcare team if you have any questions or concerns.

How is kidney pain different from back pain?

Kidney pain and back pain can feel similar but there are some differences.

• Location: back pain can be felt anywhere from the base of your neck to your tailbone, while kidney pain tends to be in one or both sides of your spine, under the ribs.
• Movement: back pain may change with different movements, such as bending over or standing up; kidney pain doesn’t usually feel different when you move.
• Other symptoms: kidney pain may come with other symptoms, such as fever, vomiting and problems with passing urine.

What should I do if I feel kidney pain?

Always see your doctor so they can work out what’s causing it.

Ask for an urgent appointment or call NHS 111 if you:

• notice blood in your urine
• have pain in your lower abdomen or back
• have a very high or very low temperature
• are feeling or being sick
• haven’t passed urine all day
• are pregnant

What tests might be done to investigate kidney pain?

Your doctor may carry out:

• urine tests (to check for infection or blood)
• blood tests (to assess kidney function and inflammation)
• imaging tests such as a kidney ultrasound or CT scan (to look for stones or narrowed areas)

What painkillers can I take?

If you have CKD, it’s important to choose pain relief carefully as some types may not be suitable.

• Paracetamol in standard doses is usually the safest first option – check with your healthcare team or pharmacist.
• NSAIDs (aspirin, ibuprofen, diclofenac, naproxen), as tablets, creams or gels, are best avoided if you have kidney disease or a kidney transplant as they can make your kidney function worse.
• If you need stronger pain relief, your healthcare team may prescribe small doses of opioid medications.