Flank Pain

Flank pain, a discomfort or ache on either side of the body between the upper abdomen and the back, is often a sign of issues within the kidneys or surrounding structures. This type of pain can vary in intensity from a mild ache to severe discomfort and can be indicative of both minor ailments and more serious health conditions.

What is Flank Pain?

Flank pain refers to discomfort in your side, between the ribs and hip. It is typically felt on one side of the body and can radiate to other areas. It often increases in intensity with movement or when pressure is applied.

Because of its association with the kidneys, flank pain is commonly considered in relation to urinary tract health.

Common Causes of Flank Pain

Flank pain can be triggered by a variety of health issues ranging from temporary muscle strains to chronic medical conditions:

  • Kidney Stones: Small, hard mineral deposits that form in the kidneys, often causing severe pain as they pass through the urinary tract.
  • Kidney Infection (Pyelonephritis): An infection that starts in the urinary tract and spreads to the kidneys, leading to pain, fever, and nausea.
  • Hydronephrosis: Swelling of a kidney due to a urine buildup, often caused by obstruction in the urinary tract like kidney stones or tumors.
  • Musculoskeletal Problems: Strained muscles, herniated discs, or fractures can cause flank pain, usually exacerbated by physical activity.
  • Urinary Tract Infection (UTI): Infections in the urinary system can cause pain along with other symptoms like burning during urination and frequent urge to urinate.
  • Kidney Cancer or Tumors: Rarely, flank pain can be a sign of cancer in the kidney or surrounding tissues.

Symptoms Associated with Flank Pain

The experience of flank pain may come with other symptoms, which vary depending on the underlying cause:

  • Severe, Colicky Pain: Often related to kidney stones.
  • Fever and Chills: Typically associated with infections.
  • Painful Urination: Common in UTIs.
  • Blood in the Urine: Can occur with kidney stones, infections, or tumors.
  • Nausea and Vomiting: Especially common with kidney stones.
  • Changes in Urination: Such as urgency, frequency, or the appearance of urine.

Diagnosing Flank Pain

Identifying the correct cause of flank pain involves several steps, often starting with a physical examination and medical history. Additional tests can include:

  • Urinalysis: To check for signs of infection, blood, or crystals that form kidney stones.
  • Blood Tests: To assess kidney function and look for signs of infection or other abnormalities.
  • Imaging Tests: Ultrasound, X-rays, CT scans, or MRI to view the kidneys and surrounding organs.
  • Cystoscopy: A scope used to see inside the bladder and urethra.

Treatment Options

Treatment for flank pain will depend on the diagnosed cause:

  • Hydration and Pain Relief: For mild cases of kidney stones, increasing water intake and using pain relievers can be enough.
  • Antibiotics: Used to treat infections of the kidneys or urinary tract.
  • Hospitalization: For severe infections or cases where significant obstruction is found, more intensive treatment may be required.
  • Surgical Interventions: For removing blockages such as stones or tumors, or for repairing structural issues in the kidneys or urinary tract.

Preventive Measures

Preventing flank pain often involves managing risk factors for kidney issues:

  • Stay Hydrated: Drinking plenty of fluids, especially water, helps prevent kidney stones and UTIs.
  • Healthy Diet: Reducing salt intake and eating fewer animal proteins may help prevent kidney stone formation.
  • Regular Check-ups: Especially for those with a history of kidney issues or who are at risk of chronic kidney disease.


Flank pain is a serious symptom that should not be ignored. It may signify a minor issue or a more severe condition requiring prompt medical attention. Understanding the potential causes and associated symptoms can help you seek timely medical advice and treatment.

If you experience persistent or severe flank pain, especially with other symptoms like fever or nausea, consulting a healthcare professional is crucial.