Flank Pain

What is flank pain?

Flank pain is pain in one or both sides of your abdomen. Certain injuries, diseases and infections can cause pain in your flanks.

Flank pain can range from mild to severe — it may be a dull ache or a sharp pain. It may come and go. It’s usually worse on one side. But it can occur on both flanks.

Where are the flanks located?

Your flanks are the areas on the sides and back of your abdomen, between your lower ribs and your hips.

How common is flank pain?

Flank pain is very common. Most people get flank pain at some point in their lives. It’s usually not a cause for concern. But it’s a good idea to reach out to a healthcare provider if you have severe flank pain that lasts more than a few days.

What does it mean when your flank hurts?

Pain in your flanks usually means you sustained an injury or have a condition or disease. The most common causes of flank pain include:

• Obstructions in your urinary system, such as kidney stones or ureteral stones.
• Urinary tract infections (UTIs), including a kidney infection.
• Back problems, including arthritis, muscle spasms, fractured spine, herniated disk and a pinched nerve.
• Diseases, including liver disease, gallbladder disease, kidney cancer, degenerative disk disease and renal artery disease.
• Shingles.
• Abdominal aortic aneurysm.

What organs can cause flank pain?

Conditions that affect the following organs can cause flank pain:

• Kidneys.
• Liver.
• Urinary bladder.
• Gallbladder.
• Pancreas.

Can flank pain be muscular?

Yes, muscle strains (pulled muscles) commonly cause flank pain. Strained back muscles may cause back pain, which can radiate away from your muscles and affect your flanks. Strained back muscles are common if you’re active in sports or work out a lot.

How will a healthcare provider determine the cause of my flank pain?

A healthcare provider will review your health history and perform a physical examination. They may ask questions like:

• Do you have left flank pain, right flank pain or pain in both flanks?
• Where exactly do you feel pain?
• Does the pain get better or worse during certain activities?
• Do you have any other symptoms in addition to flank pain?

A provider may order several tests to help diagnose the cause of your flank pain. These tests may include:

• Basic metabolic panel (BMP). A BMP is a type of blood test that helps determine if your kidneys are working properly.
• Complete blood count (CBC) and urinalysis. These tests help determine how well your organs work and check for signs of infection, cancer and other diseases.
• Imaging tests. A computed tomography (CT) scan or ultrasound can help diagnose kidney stones and determine their size and shape. A spine X-ray or magnetic resonance imaging (MRI) scan can show detailed images of injuries or abnormalities in your spine.
• Cystoscopy. A provider inserts a small tube with a light and camera at one end (cystoscope) into your urethra to look inside your bladder and diagnose problems in your lower urinary system.

How is flank pain treated?

Treatment depends on what’s causing your flank pain. A healthcare provider may recommend:

• Rest and pain medications to treat a back sprain or strain.
• Antibiotics to treat an infection.
• Drinking extra water or extracorporeal shockwave lithotripsy to help pass a kidney stone or having a minimally invasive procedure such as ureteroscopy to remove a stone.
• Chemotherapy, radiation therapy or surgery to treat cancer.

How do you relieve muscle pain in the flank?

You can help relieve muscle pain in your flank with over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) or prescription pain medicines (analgesics). Not everyone can take NSAIDs, so it’s a good idea to talk to a healthcare provider before taking any medications. If you have a history of kidney disease, you should avoid over-the-counter anti-inflammatory pain medications, including aspirin (Bayer®) ibuprofen (Advil®, Motrin®) and naproxen (Aleve®).

Stretching, exercise and physical therapy can also strengthen the muscles in your spine and help you avoid another injury.

Can flank pain be prevented?

You may not be able to prevent every cause of flank pain. But you can reduce your risk of kidney problems, injuries and diseases by:

• Staying hydrated and maintaining good eating patterns. You can lower your risk of developing kidney stones by drinking lots of water, drinking alcohol in moderation and avoiding foods that have a lot of sodium (salt).
• Maintain a weight that’s healthy for you. Regular activity and stretching help keep your body mass index (BMI) below 30. Having overweight/obesity increases your risk of developing kidney stones. It also puts pressure on your spine and makes you more vulnerable to injuries that cause flank pain.
• Take care of your urinary system. You can reduce the risk of bacteria entering your urinary system and causing a UTI by always peeing immediately after having sexual intercourse. If you have a vagina, make sure to wipe from front to back after using the bathroom. It’s also a good idea to use the bathroom as soon as you feel the urge. Holding your pee increases your chance of developing an infection.
• Visit a healthcare provider. Stay up to date on vaccines (including the shingles vaccine). Schedule regular screenings for cancer and other diseases. Talk to a provider about how to reduce your risk of kidney problems.

When should flank pain be treated by a healthcare provider?

Reach out to a healthcare provider if flank pain:

• Doesn’t go away after about a day or it goes away and comes back.
• Is severe or comes on suddenly.
• Makes it difficult for you to do everyday activities.

Flank pain that occurs along with other symptoms may be a sign of a serious health condition. Call a provider right away if you have flank pain and:

• Blood in your pee (hematuria).
• Pain or a burning feeling when you pee (dysuria).
• Diarrhea, constipation or bloating.
• Fever, chills or dizziness.
• Peeing more than usual (urgency).
• Headaches.
• Nausea and vomiting.
• Skin rash (contact dermatitis).

How do I know if I have flank, muscle or kidney pain?

A muscle strain can cause flank pain. Your kidneys are usually below your ribcage, behind your belly. Most people have one on either side of your spine. You usually feel kidney pain on one side. A muscle strain that causes flank pain often worsens with certain movements, such as bending, twisting, lifting heavy weight, laughing or sneezing. Kidney pain doesn’t usually get worse with movements.

What are musculoskeletal flank pain symptoms?

Flank pain that relates to your muscles and skeleton (musculoskeletal flank pain) usually feels more like a dull ache. It often worsens when you perform specific movements or apply pressure to the area.