Epidural steroid injections

An epidural steroid injection places a small dose of steroid medicine into the epidural space. That is a thin layer of fat and blood vessels just outside the fluid-filled sac that holds the spinal cord and nerves. The steroid is a strong anti-inflammatory, similar to a hormone your body makes on its own. It is not the kind of steroid some athletes misuse to build muscle. It is usually mixed with a numbing medicine.

These injections are most often used for pain that travels from the low back down a leg (often called sciatica), or from the neck down an arm, when a clinician suspects an irritated spinal nerve. That irritation often comes from a disc that bulges or leaks, or from narrowing of the spaces the nerves pass through, called stenosis.

The injection is usually guided by a live x-ray, called fluoroscopy, so the needle reaches the right spot. The medicine can be placed from the back of the spine between two bones, from the side where a nerve exits, or from near the tailbone. The clinician chooses the path based on where the problem is.

Specialists in pain medicine, physical medicine and rehabilitation, anesthesiology, or radiology usually perform these injections.

When a disc or narrowing presses on a spinal nerve, the nerve can become inflamed and more sensitive, and it sends pain down the arm or leg. Researchers think the steroid works mainly by calming that inflammation, but they are not sure. In some trials, numbing medicine alone helped about as much.

The numbing medicine can bring relief within minutes, but it wears off within hours.

An injection does not repair a disc or widen a narrow space. The hope is to turn the pain down enough to move more comfortably and keep up with physical therapy while the body settles. Disc material that has pushed out or broken off often shrinks on its own over months. A disc that only bulges shrinks less often, and narrowing from stenosis usually does not go away.

Before

Your care team will ask about blood thinners, diabetes, allergies (especially to contrast dye or numbing medicine), recent infections, and whether you could be pregnant.

Some blood thinners are paused for a few days before certain injections, and some are not. The team will tell you what to do. Never stop a blood thinner on your own.

Many clinics ask you to bring a driver, because the numbing medicine can leave an arm or leg numb or weak for a few hours. A driver is usually required if you are given medicine to help you relax.

During

You usually lie face down on a padded table, or on your back or side for some neck injections. The skin is cleaned and numbed first. Most people feel a quick sting, then pressure.

A small amount of contrast dye is often used to check where the medicine will spread before the steroid goes in. Some people feel a brief flash of their familiar pain, or pressure down the arm or leg, as the medicine goes in.

The injection itself usually takes less than half an hour. Plan to be at the clinic longer, to allow time for check-in and a short rest afterward.

After

The numbing medicine can leave the arm or leg feeling numb, heavy, or weak for a few hours. Soreness where the needle went in is common for a day or two.

Pain can feel a bit worse for a day or two afterward. If the steroid helps, it usually starts to work within a few days, and sometimes takes a week or two.

Most people return to light, everyday activity the next day. A simple pain diary for the first couple of weeks helps you and your clinician judge how much it helped.

For leg pain from an irritated nerve in the low back, studies show that epidural steroid injections give, on average, a small amount of extra pain relief compared with a placebo injection. That extra relief shows up in the first weeks. ^{[1] [2]}

A 2025 American Academy of Neurology review found that injections probably improve pain and daily function for up to three months in people with pain from an irritated spinal nerve. Most evidence came from the low back, with fewer neck studies. It found possible improvement in daily function at six months or longer, but too little evidence to know whether pain relief lasts that long. ^[18]

Averages hide a wide range. Some people feel much better after an injection and others notice little change. Part of the improvement people feel comes from healing that often happens anyway, and no test can yet predict who will do well.

For spinal stenosis in the low back, where narrowing causes leg pain with standing or walking, a large trial found little or no extra short-term pain relief from adding steroid to numbing medicine. ^[5] The AAN review found possible short- and longer-term improvement in daily function, while longer-term pain benefit remains uncertain. Evidence for spinal stenosis in the neck was too limited to judge. ^[18]

For leg or arm pain that has lasted more than 3 months, a 2025 review of many trials found little or no extra relief from epidural injections compared with a sham (pretend) procedure, and an international guideline strongly recommended against them for pain lasting that long. That guideline does not cover newer pain, and pain specialty societies have disputed it. NICE, a UK guideline group, supports considering an epidural injection for new, severe sciatica, and advises against it for leg symptoms brought on by standing or walking from narrowing of the central spinal canal. ^[19]

Injections may slightly lower the chance of having surgery in the short term. Studies have not shown that they prevent surgery in the long run.

For back or neck pain that does not travel down an arm or a leg, epidural steroid injections are generally not recommended. Most research is on the low back. There is less research on epidural injections in the neck.

Many clinicians use an injection as a bridge: a way to make it easier to stay active and do physical therapy, rather than a treatment on its own.

Common and short lived

• Soreness at the injection site for a day or two.
• A short-term increase in pain.
• Flushing of the face and chest, feeling warm, or trouble sleeping for a few nights.
• Higher blood sugar for a day or two in people with diabetes, so checking more often during that time helps.
• Temporary numbness or heaviness in the arm or leg from the numbing medicine.

Less common

• A headache if the needle passes through the fluid-filled sac around the nerves. It often goes away on its own within days, and sometimes needs a follow-up treatment called a blood patch.
• Changes in menstrual periods.

Rare but serious

• Infection, bleeding near the spine, or nerve injury.
• Very rarely, stroke, paralysis, loss of vision, or death have been reported after epidural steroid injections. In 2014 the US Food and Drug Administration added a warning about these events to injectable steroid labels. Specialists have agreed on safety steps to lower this risk, such as imaging guidance and choosing certain steroid types for some injections.

Other downsides

• Relief is often temporary, and the same pain can come back.
• Steroid doses add up. Many clinicians limit how many injections someone has in a year, partly because of effects on blood sugar and bone health.

Get emergency care right away for numbness or weakness in the arms or legs that is getting worse or has not worn off when your team said it would, new trouble controlling your bladder or bowels, numbness in the groin, genitals or buttocks, severe new back or neck pain, a fever with a stiff neck or severe headache, or signs of a stroke such as loss of balance, vision changes, a drooping face, or trouble speaking. Call your care team the same day for a fever, redness or drainage at the injection site, or a headache that gets worse when you sit or stand.