What should you know about flank pain: what is it?

The flank contains muscles, ribs, nerves, bowel, and structures connected with the urinary system. Pain may be dull, cramping, sharp, or steady, and it may spread toward the abdomen or groin. [Kidney Stones](/conditions/kidney-stones/) can cause intense, wave-like pain, while [Kidney Infection](/conditions/kidney-infection/) may present with flank pain alongside fever or urinary changes. A [Urinary Tract Infection](/conditions/urinary-tract-infection/) can cause urinary discomfort and may sometimes be associated with pain higher in the urinary tract. A pulled muscle is another possible source, especially after unusual activity.

Note which side hurts, when it began, whether it travels, and whether movement, coughing, breathing, meals, or urination affects it. Record fever, nausea, vomiting, urine colour, and any injury. Gentle activity may be reasonable for mild pain that follows strain, but stop if it worsens. Arrange a clinical review when pain persists, returns, or has no clear trigger; the examination may guide urine testing or imaging.

Seek urgent care for severe or sudden pain, fever with flank pain, repeated vomiting, faintness, confusion, inability to pass urine, or blood in the urine. Get prompt advice after a significant injury or during pregnancy. New flank pain with breathing trouble or chest pain also needs urgent assessment.

What structures could be causing this pain? Which symptoms would point toward a urinary cause? Do I need a urine test, blood test, or scan? What activity is safe while I recover?