Sharp pain in the flank area: what to know

The flank is the side of the body between the ribs and hip. A pulled muscle may hurt more with movement, twisting or touch. Kidney stones can cause intense waves of pain that travel toward the lower abdomen or groin. Kidney Infection may cause flank pain with fever, chills, nausea or feeling unwell. Urinary Tract Infection can cause burning, urgency or frequent urination and may spread upward. Pain can also come from nearby abdominal or back structures, so location alone cannot confirm a kidney problem.

Stop activities that increase the pain and note whether movement changes it. Drink normally unless a clinician has told you to restrict fluids; do not force large amounts when nauseated. Record urine colour, frequency, burning, blood, fever and whether pain comes in waves. Arrange a medical review if pain persists, returns, or is accompanied by urinary symptoms. A clinician may examine your abdomen and back and test urine to distinguish infection, stones and other causes.

Seek urgent care for flank pain with fever or chills, repeated vomiting, visible blood in urine, inability to pass urine, severe worsening pain, faintness, confusion or marked weakness. Prompt assessment is also needed if you have one functioning kidney, are pregnant, or have significant kidney disease. A blocked urinary passage with infection can become serious, so do not wait for symptoms to settle on their own.

Ask whether the pain pattern suggests muscle strain, a stone or infection; whether urine testing or imaging is needed; which fluids and pain relief are suitable; and which symptoms should bring you back urgently.