Kidney Pain vs. Back Pain: How to Tell the Difference

Kidney pain is most often caused by a kidney infection or a stone in the tubes coming out of your kidney. It can also have a variety of other causes.

Where the pain is located

Kidney pain is often felt in your flank, the area on either side of your spine between the bottom of your rib cage and your hips. It may also occur in your side, abdomen, or lower back.

The pain usually occurs on one side of your body, but it can occur on both sides.

Type of pain

Kidney pain is usually sharp if you have a kidney stone and a dull ache if you have an infection. Most often, it will be constant.

If you’re passing a kidney stone, your pain may fluctuate as the stone moves. With other conditions, such as polycystic kidney disease, you may have periods of severe pain.

If kidney cancer is causing your pain, it may feel like a persistent dull ache that extends from the middle of your back to the bottom of your ribs.

Radiation of the pain

Sometimes the pain radiates or spreads, to your inner thigh or lower abdomen.

Severity of the pain

Kidney pain is classified according to how bad it is — severe or mild. A kidney stone or cyst can cause severe pain, while the pain from an infection is usually mild.

Things that make it better or worse

Typically, nothing improves kidney pain until the problem is corrected, such as passing the stone, using medications to resolve an infection, or getting other treatment.

Unlike back pain, kidney pain usually won’t change with movement.

Accompanying symptoms

If you have a kidney condition, there are several common symptoms:

• fever and chills
• nausea and vomiting
• cloudy or dark urine
• an urgent need to urinate
• pain when you urinate
• a recent infection in your bladder
• blood in your urine
• small stones that look like gravel in your urine (if you have a kidney stone)

With kidney cancer, you may also feel tired or have a lump on your lower back or side. Symptoms may not appear until later stages.

Polycystic kidney disease (PKD) may also cause no symptoms until the cysts it causes have become larger. The condition may lead to:

• pain in your stomach or lower back
• high blood pressure
• kidney stones
• kidney failure

Back pain is more common than kidney pain and is usually caused by a problem in the muscles, bones, or nerves in your back.

Where the pain is located

Pain can occur anywhere on your back, but it’s most commonly located in your lower back or buttocks.

Type of pain

Muscle pain feels like a throbbing ache. If a nerve has been injured or irritated, the pain is a sharp burning sensation that may travel down your buttock to your lower leg or even your foot.

Muscle pain may affect one or both sides, but nerve pain usually only affects one side.

With osteoarthritis (OA), the pain will likely worsen as your condition develops. Your back may feel more stiff and painful in the mornings.

Traveling pain

Pain from herniated discs and nerve problems may spread to your lower leg. Muscle pain usually stays in your back.

Severity of the pain

Back pain is described as acute or chronic based on how long you’ve had it.

Acute pain, the most common, lasts a few days to a few weeks and typically improves by itself. Subacute pain lasts between 4 weeks and 6 months. Chronic pain lasts longer than 3 months.

Things that make it better or worse

Back pain may worsen with movement or if you sit or stand for a long time. It may get better if you change positions, walk around, or switch to activities that reduce stress on your back.

With certain conditions, such as sciatica (a nerve problem), your pain may worsen if you bend over or cough.

Accompanying symptoms

Other symptoms you may experience with back pain include:

• the painful spot looking swollen and feeling tender to the touch
• a muscle spasm in the painful area
• stiffness in your back
• numbness or weakness in one or both of your legs (if the pain is due to a nerve issue such as sciatica)
• a grinding feeling when you move (if the pain is due to OA)

If you have back pain and can’t hold your urine or bowel movements, something is pressing on your spinal nerves, and you should get medical care immediately.

This condition, called cauda equina syndrome, can cause severe long-term damage to your spinal nerves if not treated right away.

Kidney and back pain may sometimes feel similar, but the conditions that cause them are usually very different.

It’s important to understand the cause of your pain so you can treat it appropriately.

Kidney pain causes

A variety of conditions may cause one or both of your kidneys to hurt, including:

• Hydronephrosis: Urine can build up in one or both of your kidneys due to a blockage, causing kidney swelling.
• Kidney cancer: Cancer can start in your kidneys and affect one or both.
• Pyelonephritis: This is when a urinary tract infection (UTI) moves up into one or both of your kidneys.
• Kidney stones: These can form in one or both of your kidneys from minerals. They vary in size and may cause pain as they pass through your urinary tract.
• Polycystic kidney disease: This is a genetic condition in which cysts grow in both of your kidneys and may eventually cause kidney failure.

Back pain causes

There are many potential causes of back pain. They range from genetic issues to injuries to degenerative or nerve problems. A few of these include:

• Spine irregularities: An abnormal curve to your spine from conditions such as scoliosis can result in back pain.
• Injury or strain: Falling, being in an accident, or picking up something heavy can damage your muscles, the tendons or the connective tissues between the muscles and bones, or your spine.
• OA: This is when the cartilage between your joints breaks down, leading to stiffness and pain as your bones rub against each other.
• Sciatica: This involves pressure on your sciatic nerve, which runs from your lower back down your legs. This can cause pain in your back and your leg.
• Herniated disc (slipped disc): If the discs that provide cushioning between your vertebrae are compressed, they can be pushed outward. This can affect your nerves or spinal cord, resulting in pain.

The treatment for either kidney or back pain will depend on the cause of your pain. Medications and natural treatments can help many types of kidney and back pain. Surgery can be another option in some cases.

Kidney pain

Some kidney conditions can be treated with medications such as:

• antibiotics if you have a kidney infection
• blood pressure medications, which may be needed for high blood pressure caused by polycystic kidney disease
• immunotherapy drugs for kidney cancer

Other drugs for kidney cancer include targeted drugs such as sorafenib (Nexavar) or pazopanib (Votrient).

Conditions such as polycystic kidney disease, hydronephrosis, or cancer may damage your kidney enough that you may need surgery to remove it. You can live a healthy life with one kidney, or you may have a kidney transplant.

Other types of surgery for kidney cancer may remove just the section of your kidney where the cancer is located.

Unless you have kidney failure, it’s important to drink plenty of water to help treat and prevent kidney stones and infections. Eating a healthy diet and maintaining a moderate weight may help prevent kidney cancer and kidney stones.

Learn more about nutrition for kidney cancer and kidney removal.

Back pain

Pain relief medications are common back pain treatments, including acetaminophen, nonsteroidal anti-inflammatory drugs such as Advil, or injected steroids. Muscle relaxants may also help.

Surgery may be beneficial in some cases, such as to fuse spine sections together for stabilization for OA or to correct a spinal curve from scoliosis. Surgery can also remove the pressure from a herniated disc on a nerve.

You can often also improve back pain through natural and lifestyle remedies, including:

• physical therapy and exercises that strengthen your core
• acupuncture
• massage
• hot or cold packs
• sticking to activities that limit stress on your back
• losing weight, if needed

Especially if you think your pain is coming from your kidney, consider seeing a doctor or healthcare professional for an evaluation and treatment.

A doctor may use one of the following to help determine the cause of your pain:

• a urine test to look for minerals, blood, or an infection
• a blood test to check for normal kidney function
• a CT scan or ultrasound

It’s important to get medical care if the pain is centered on your kidney or if you have a kidney infection or kidney stone.

You may be able to treat short-term back pain on your own, but if it doesn’t get better, is more than mild pain, or spreads, it’s best to see a doctor.

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