How do I distinguish kidney pain from back pain?

Kidney pain is located more laterally in the flank and may radiate to the lower abdomen, whereas back pain often changes with movement. However, a reliable distinction can only be made through medical examination.

Can kidney stones pass on their own?

Small stones frequently pass on their own with plenty of fluids. Larger stones or severe symptoms require medical supervision.

Does drinking plenty of fluids help with kidney pain?

For many causes, drinking plenty of fluids supports the urinary tract. However, in cases of urinary retention this may be unfavorable, which is why the cause should be clarified first.

Kidney / Flank Pain — Causes, Assessment & the Right Specialty

Pain in the flank, meaning the side area between the ribs and hips, is often attributed to the kidneys. It can originate from the kidneys or ureters, for example due to a kidney stone, but may also have a muscular cause. How the pain progresses – dull and persistent or wave-like and cramping – and whether accompanying symptoms occur helps with classification. A medical assessment will clarify the cause and determine further steps.

Possible causes

Kidney stones

A stone in the ureter often causes severe, wave-like pain that may radiate to the groin or lower abdomen.

Urinary tract or kidney infection

If an infection ascends to the kidney, flank pain develops, often accompanied by fever and feeling unwell.

Muscular or spinal cause

Tension or irritation in the back area can feel like kidney pain without the kidney being affected.

Urinary obstruction

If urine drainage is obstructed, it backs up and stretches the kidney, which can trigger dull to severe pain.

Typical steps at the doctor's office

1During the consultation and examination, the location, radiation and progression of the pain are assessed and the flank is palpated.
2A urine test reveals signs of blood, crystals or inflammation; a blood test complements the picture.
3An ultrasound examination of the kidneys makes urinary retention or stones visible; if necessary, further imaging follows.

What you can do yourself

Drink sufficient fluids throughout the day, unless medically advised otherwise, to flush the urinary tract.
Heat, such as a hot water bottle on the flank, can have a soothing effect for muscular complaints.
If fever, chills, persistent vomiting, or blood in the urine occur in addition, please contact us immediately — do not wait until the scheduled appointment.
Rest if you have acute, severe pain and wait until after medical evaluation before physical exertion.

When a doctor's visit makes sense

Flank pain together with fever or chills, very severe wave-like pain with vomiting, or pain when you can barely pass water, should be seen at an emergency department the same day — an infected or obstructed kidney must be treated quickly. Persistent or recurring flank pain should be medically assessed, especially if blood in the urine or discomfort when passing water is also present. The family doctor's practice or urology is responsible for this.

Frequently asked questions

How do I distinguish kidney pain from back pain?: Kidney pain is located more laterally in the flank and may radiate to the lower abdomen, whereas back pain often changes with movement. However, a reliable distinction can only be made through medical examination.
Can kidney stones pass on their own?: Small stones frequently pass on their own with plenty of fluids. Larger stones or severe symptoms require medical supervision.
Does drinking plenty of fluids help with kidney pain?: For many causes, drinking plenty of fluids supports the urinary tract. However, in cases of urinary retention this may be unfavorable, which is why the cause should be clarified first.

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