What should you know about spasmodic flank pain?

Flank pain is felt between the ribs and the hip, usually on one side of the back or side. Pain that rises and eases in waves can occur when a kidney stone moves through the urinary tract. A kidney infection may cause flank pain with fever, chills, feeling unwell, or urinary changes. A urinary tract infection can cause burning or frequent urination and may spread upwards if untreated.

Muscle strain, nerve irritation, and problems in nearby abdominal organs can also cause pain in this area. The location alone cannot identify the cause. A clinician may ask when the pain began, whether it travels toward the groin, and whether urine looks different.

Rest in a comfortable position and record when each spasm starts, how long it lasts, and where it travels. Sip fluids if you can keep them down, but do not force fluids during repeated vomiting or if a clinician has restricted your intake. Use only pain medicine that is suitable for you and follow its label or medical advice.

Arrange medical assessment if the pain is new, recurring, or interfering with normal activity. A clinician may check your abdomen and back, urine, temperature, and hydration. Further tests may be considered when a stone, infection, or another condition is suspected.

Seek urgent help for severe or worsening pain, fever with flank pain, repeated vomiting, faintness, confusion, very little urine, blood in the urine, or pain during pregnancy. Prompt care is especially important when urinary symptoms occur with fever or when you have one functioning kidney or known kidney disease.

Ask which symptoms suggest a kidney stone or infection, whether you need a urine test or imaging, which pain medicines are appropriate for you, and what changes should prompt immediate reassessment.