When Should You Be Worried About Flank Pain?
It’s natural to feel concerned when you experience persistent flank pain, especially when you’re unsure if it requires medical attention. As someone who might be experiencing this discomfort right now, you deserve clear guidance on when to seek help.
Common reasons for concern with flank pain include:
- Severe, sudden pain that feels different from muscle soreness
- Pain accompanied by fever, chills, or nausea
- Discomfort that persists for more than a few days
- Pain coupled with burning during urination or blood in your urine
- Flank pain that worsens with movement or deep breathing
Don’t let uncertainty about your symptoms keep you from getting the care you need. Complete Care’s emergency-trained physicians are available around the clock to provide prompt, thorough emergency treatment for flank pain no matter which of our freestanding ER locations you visit in Texas or Colorado.
For life-threatening situations, please call 911.
What is flank pain?
Flank pain occurs in your side, specifically in the area between your lower ribs and hip, and can range from mild discomfort to debilitating pain. Think of it as the part of your body where your “love handles” might be. This important region of your body houses several organs, including your kidneys, and can be found on both the left and right sides of your torso.
Flank pain can occur on one or both sides, and it may spread to your lower back or abdomen, depending on the root cause. The sensation can also vary depending on the cause — some people describe it as cramping or throbbing, while others might feel more of a stabbing pain. You might notice it gets worse when you move around, take deep breaths, or press on the area. Because this region contains several important organs and muscles, it’s important to pay attention to any persistent or severe pain in this area.
How do I know if my flank pain is serious?
1. Severe, sudden pain
When severe, sudden flank pain strikes, it often feels like an intense, sharp sensation that comes on without warning. This type of pain, whether presenting as left flank pain or right flank pain, can be so intense that it stops you in your tracks and may even make it difficult to find a comfortable position. The pain might feel like someone is squeezing your side or like you’ve been struck in the area.
This sudden onset of severe pain could indicate several urgent conditions, including kidney stones, a ruptured cyst, or, in some cases, a serious infection. If the pain is particularly severe on one side, whether right or left side pain, it could also signal other underlying conditions that require immediate medical attention, like a kidney infection or, less commonly, an abdominal aortic aneurysm.
2. Pain accompanied by fever, chills, or nausea
When flank pain occurs alongside a high fever, chills, or nausea and vomiting, it often indicates that your body is fighting an infection. These symptoms commonly appear together and may get worse over hours or days. You might notice that you’re alternating between feeling hot and cold, experiencing uncontrollable shivering, or feeling queasy and unable to keep food down.
This combination of symptoms frequently points to a kidney infection or other serious infections that require prompt medical attention. The presence of fever above 101.5°F (38.6°C) alongside flank pain is particularly concerning and should never be ignored, as it could indicate that the infection is becoming severe.
3. Discomfort that persists for more than a few days
Persistent flank pain that lasts longer than a few days may start as a mild annoyance but can develop into a more serious concern. You might notice that the pain ebbs and flows but never fully goes away or that certain positions and activities consistently trigger or worsen the discomfort. This type of ongoing pain might be mild enough that you can continue your daily activities, but it serves as a warning sign that something isn’t right.
Chronic flank pain could indicate several underlying conditions, from musculoskeletal problems to ongoing kidney issues. If the pain persists beyond three days, it’s important to have it looked at, as chronic pain can be a sign of conditions that may worsen without proper treatment, such as kidney stones that haven’t passed or chronic urinary tract infections.
4. Pain coupled with burning during urination or blood in your urine
When flank pain occurs alongside urinary symptoms, particularly burning during urination or blood in the urine (hematuria), it often indicates a problem within your urinary tract. You might notice that your urine appears pink, red, or cola-colored or that you feel a burning or stinging sensation every time you use the bathroom. These symptoms might be accompanied by an increased urge to urinate or difficulty emptying your bladder completely.
This combination of symptoms frequently indicates a urinary tract infection that has potentially spread to the kidneys, or it could signal the presence of kidney stones. In some cases, these symptoms might also indicate more serious conditions affecting the urinary tract or kidneys that require medical evaluation.
5. Flank pain that worsens with movement or deep breathing
Pain that intensifies with movement or deep breathing often indicates the involvement of the muscles, bones, or other structures in your chest and abdominal wall. You might notice that certain movements, like bending, twisting, or reaching, cause sharp increases in pain. Taking deep breaths, coughing, or laughing might also trigger or worsen the discomfort.
While this type of pain might be due to muscle strain or inflammation of the rib cage, it could also indicate more serious conditions affecting your lungs or other organs. If the pain significantly limits your ability to move or breathe normally, it’s important to seek medical attention to rule out conditions like pneumonia, pleurisy, or other respiratory issues.
6. Pain after an injury, fall, or accident
Flank pain that starts after a fall, car accident, or blow to the side needs prompt evaluation. Your kidneys sit close to the surface of your back and can be bruised or injured by impact.
Watch for blood in your urine, worsening pain, dizziness, or bruising on your side or back. These can be signs of internal injury that isn’t visible from the outside.
What could be causing your flank pain?
The most common causes of flank pain are kidney stones, kidney infections, urinary tract infections, and muscle strains. How your pain feels and what other symptoms you have can offer clues about the cause. Only a medical evaluation can confirm a diagnosis, but here’s how these conditions often show up:
Kidney stones
Kidney stone pain often comes in intense waves that build, ease off, and return. It usually starts in your side or back and may move toward your lower abdomen or groin as the stone travels. Nausea, vomiting, and blood in your urine are common.
Kidney infection
A kidney infection usually causes a deep, steady ache in one side along with fever and chills. You may also have burning during urination, cloudy or foul-smelling urine, and nausea. Kidney infections need antibiotics and can become serious if they aren’t treated.
Urinary tract infection
A urinary tract infection usually starts in the bladder, causing burning, urgency, and frequent urination. When flank pain joins those symptoms, it may mean the infection has moved up toward your kidneys.
Muscle strain
Muscle-related flank pain usually starts after lifting, twisting, or exercising. The area often feels tender to the touch, and the pain gets worse with certain movements. It tends to improve with rest and doesn’t come with fever or urinary symptoms.
Shingles
Shingles can cause burning or tingling pain on one side of your body before a rash appears. The rash usually shows up a few days later in a band or stripe across the side or back.
Abdominal aortic aneurysm
An abdominal aortic aneurysm is a bulge in the body’s main artery. If it ruptures, it can cause sudden, severe pain in the abdomen, side, or back that some people describe as tearing. Dizziness, fainting, or a racing heart may follow.
This is a life-threatening emergency. Call 911.
When should I go to the ER for flank pain?
Living with flank pain can be concerning, and knowing when to seek emergency care isn’t always clear. While some causes of flank pain can be managed at home, certain symptoms indicate a need for immediate medical attention from your nearest ER.
- Severe, intense pain accompanied by a fever over 101.5°F
- Uncontrolled nausea or vomiting
- Chills, severe shaking, confusion, or extreme fatigue
- Blood in your urine, complete inability to urinate, or severe burning with urination
- Flank pain that occurs after an injury, fall, or accident
- Pain so severe that it prevents basic movements
- Rapid heart rate, dizziness, or pale/clammy skin
While it might be tempting to “wait it out” or see if symptoms improve on their own, certain conditions that cause flank pain can quickly become serious without proper treatment. When it comes to severe pain or concerning symptoms, it’s always better to err on the side of caution and get evaluated by medical professionals who can properly diagnose and treat the underlying cause.
What can Complete Care do for severe flank pain?
At Complete Care, our freestanding ERs have the same imaging and lab capabilities as a hospital ER and treat everything from kidney stones to chest pain, often with shorter waits. Because everything happens under one roof, you won’t be sent somewhere else for testing or left waiting days for answers.
Here’s what your visit typically includes:
A thorough evaluation
Your physician will start by listening to your symptoms, including where the pain is, when it started, and whether it comes and goes. They’ll also ask about fever, nausea, and changes in urination, then perform a physical exam. This helps narrow down the likely cause and decide which tests you need.
On-site lab work
A urinalysis can quickly detect infection, blood, or crystals in your urine that point to kidney stones. Blood work checks how well your kidneys are working and whether an infection is spreading. Because our lab is on-site, results come back quickly, so your treatment can start sooner.
Advanced imaging
A CT scan is one of the most accurate ways to find kidney stones and see their size and location, which helps your physician decide whether a stone is likely to pass on its own. Ultrasounds can check your kidneys and nearby organs for swelling, blockages, or infection without radiation. That makes them a good option for children and pregnant patients.
Fast pain relief
Flank pain can be intense, and you shouldn’t have to wait until every result is back to feel better. Your care team can give medication to ease your pain and settle your nausea early in your visit. This helps you rest more comfortably while your team works on a diagnosis.
IV fluids
Vomiting, fever, and not being able to keep fluids down can leave you dehydrated quickly. IV fluids restore hydration faster than drinking alone. They may also help flush small kidney stones through your urinary tract.
Immediate treatment
If your tests show a kidney or urinary tract infection, antibiotics can start before you leave. Treating an infection early lowers the risk of it spreading to your bloodstream. Your physician will also make sure you have what you need to continue treatment at home.
A clear plan
Before you go home, your physician will explain what caused your pain and what your results mean. You’ll leave with clear instructions for recovery and signs to watch for. If you need more care, such as a urologist for a larger kidney stone, your team will arrange a specialist referral or a hospital transfer.
Complete Care is open 24 hours a day, 7 days a week, with no appointment needed. Our team treats both adults and children at freestanding ER locations across Texas and in Colorado Springs, so fast, expert care for flank pain is never far away.
Flank pain — FAQs
Where is the flank on your body?
Your flank is the area on each side of your body between the bottom of your ribs and the top of your hip bone. It wraps from your side toward your back, roughly where your kidneys sit. You have a flank on both the left and right side of your torso.
How can I tell if flank pain is from my kidneys or a muscle?
Kidney pain is usually deep, felt just under the ribs, and often comes with fever, nausea, or changes in urination. Muscle pain usually starts after physical activity, feels tender when you press on it, and changes with movement. If you aren’t sure, or if your pain comes with any urinary symptoms, get it evaluated.
What does it mean if flank pain is on the left or right side?
Pain on either side often involves the kidney on that side. Right-side flank pain can also come from the liver or gallbladder. Left-side pain can involve the spleen or colon. The side alone can’t confirm a cause, so other symptoms and testing matter. [link: left side abdominal pain blog]
Can a kidney infection go away on its own?
No, a kidney infection needs antibiotics to clear. Without treatment, the infection can damage your kidneys or spread to your bloodstream, which can be life-threatening. See a doctor promptly if you have flank pain with fever or urinary symptoms.
Can dehydration cause flank pain?
Dehydration can contribute to flank pain indirectly. Not drinking enough fluids makes your urine more concentrated, which raises the risk of kidney stones. Staying hydrated is one of the simplest ways to lower that risk.
Is flank pain during pregnancy an emergency?
Flank pain during pregnancy should be checked promptly, especially if you have fever, chills, or burning during urination. Pregnancy raises the risk of kidney infections, and these infections can affect both you and your baby. Call your OB or seek emergency care if your symptoms are severe.
Worried about flank pain? Complete Care has you covered 24/7!
When flank pain strikes, you deserve immediate care from medical professionals who understand your concerns. With state-of-the-art facilities across Texas (Austin, Corpus Christi, Dallas/Fort Worth, East Texas, Lubbock, and San Antonio) and in Colorado Springs, Complete Care provides immediate, expert treatment for all types of flank pain.
From advanced diagnostic capabilities to comprehensive treatment options, we’re equipped to identify and address the root cause of your discomfort. Our commitment to patient care means you’ll receive personalized attention and treatment in a comfortable, professional environment.
Don’t let flank pain impact your quality of life. Visit your nearest Complete Care location today and take the first step toward relief.
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Reviewed By:
Jeffrey Peebles, M.D.
Complete Care's health articles are based on evidence-based medical information and reviewed by Dr. Jeffrey Peebles, Medical Director of Complete Care Southlake, to ensure accuracy and alignment with current medical standards.
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