Burning flank pain: what to know

The flank is the side between the ribs and hip. A strained muscle may hurt more when you twist, lift, or press the area. Irritated nerves can produce burning, tingling, or pain that travels around the body. A urinary tract infection may cause burning when passing urine, urgency, or lower abdominal discomfort. Kidney infection can add fever, chills, nausea, or tenderness near the back. Kidney stones often cause intense waves of pain that may move towards the groin, sometimes with blood in the urine.

Note which side hurts, when it began, whether it comes in waves, and what movements change it. Drink fluids normally unless a clinician has told you to restrict them. Avoid strenuous lifting while a muscle cause is possible. Do not take antibiotics left from an earlier illness. A clinician may check your abdomen and back, test urine, and decide whether blood tests or imaging are needed.

Get urgent medical help for flank pain with fever or chills, repeated vomiting, inability to pass urine, visible blood in urine, severe worsening pain, faintness, or confusion. Seek prompt advice during pregnancy, with one functioning kidney, or if you have significant medical conditions. A rash or blisters on one side can indicate a nerve-related skin infection and should be reviewed.

Ask whether your symptoms fit a kidney infection, kidney stone, urinary infection, muscle strain, or nerve irritation; which tests are useful; how to control pain safely; and which changes require immediate care.