Back flank pain on both sides: what to know

Flank pain is felt between the ribs and hips, toward the back. Pain on both sides can follow lifting, prolonged sitting, awkward movement, or tension in the back muscles. A kidney infection often presents with flank pain together with fever, chills, feeling unwell, or painful urination. Kidney stones may cause severe waves of pain, nausea, or blood in the urine. A urinary tract infection may cause burning urination, frequent urges, or lower abdominal discomfort, although flank pain with fever needs prompt assessment.

Notice whether movement, pressing the area, meals, or urination changes the pain. Rest from heavy lifting, use gentle movement, and try a comfortable warm pack if the pain feels muscular. Drink normally unless a clinician has told you to restrict fluids. Arrange a medical assessment if the pain persists, returns, or comes with urinary changes; a clinician may examine your back and abdomen and test a urine sample.

Seek urgent care for severe or rapidly worsening pain, fever with flank pain, repeated vomiting, faintness, confusion, inability to pass urine, or visible blood in the urine. Get prompt help after an injury, during pregnancy, or if you have one functioning kidney or known kidney disease. Do not wait for pain to become unbearable before arranging assessment.

Ask what examination or urine testing is appropriate, whether your symptoms fit a kidney or muscle cause, and which pain medicines are suitable for you. Mention the start time, exact location, severity, triggers, fever, urinary symptoms, medicines, and any recent exercise or injury.