When should you see a doctor about flank pain?

Flank pain is felt between the ribs and the hip, often on one side. A muscle strain can hurt more with movement or touching the area. Pain from the urinary system may occur with burning urination, a change in urine, nausea, or pain that travels towards the groin. Kidney infection can present with flank pain and fever, while kidney stones can cause intense, wave-like pain. A urinary tract infection may cause urinary symptoms without flank pain, but pain higher in the back deserves assessment.

Note when the pain began, where it is located, whether it moves, and what makes it better or worse. Record fever, vomiting, urinary changes, recent exercise, injury, and medicines. Drink normally unless a clinician has told you to restrict fluids. Avoid taking leftover antibiotics, and ask a pharmacist or clinician which pain medicine is suitable if you have kidney disease, stomach ulcers, are pregnant, or take regular medicines.

Seek urgent medical help for severe or rapidly worsening pain, flank pain with fever or chills, repeated vomiting, confusion, fainting, blood in the urine, or difficulty passing urine. Urgent assessment is also sensible after a significant injury, during pregnancy, or when you have one functioning kidney or known kidney disease. These features can signal a problem needing prompt examination and urine or blood testing.

Ask whether the pattern suggests a muscle, urinary, or kidney cause; whether you need urine testing or imaging; which pain medicines are appropriate; and what changes should prompt a return visit. Bring a list of medicines and any home temperature readings.