Causes of lower left flank pain

Pain after lifting, twisting, coughing or exercise is more consistent with the muscles or joints of the back and side. Urinary causes may bring burning when passing urine, frequent urges, cloudy urine or pain that travels towards the groin. A kidney stone can cause severe waves of pain, while a kidney infection may cause flank tenderness with fever or feeling unwell. Bowel or reproductive-organ problems can also be felt in this area. Pain alone cannot identify the cause.

A symptom page about [Flank Pain](/symptoms/flank-pain/) can help you describe the location, timing and character of the discomfort. A [Urinary Tract Infection](/conditions/urinary-tract-infection/) can affect the urinary tract, while [Kidney Stones](/conditions/kidney-stones/) and [Kidney Infection](/conditions/kidney-infection/) need different assessments.

Note whether the pain is constant or comes in waves, whether movement changes it, and whether you have urinary, bowel or menstrual symptoms. Drink normally unless a clinician has told you to restrict fluids, and avoid strenuous lifting until the cause is clearer. Arrange medical assessment if pain persists, returns, or is accompanied by urinary changes. A clinician may examine your abdomen and back and decide whether urine testing or imaging is appropriate.

Seek urgent care for severe or rapidly worsening pain, fever with flank pain, repeated vomiting, faintness, blood in the urine, inability to pass urine, a rigid or very tender abdomen, or pain during pregnancy. These features can signal infection, blockage or another problem needing prompt treatment.

Ask: Could this be urinary, muscular or abdominal? Do I need urine testing or imaging? Which symptoms should make me return urgently? What pain relief is suitable with my other medicines?