Epidural Steroid Injection (ESI): How It Works, What to Expect, Risks, and Results
Updated: 6 days ago
Written and medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026 · How we review
Quick Answer: What is an epidural steroid injection?
An epidural steroid injection (ESI) is a procedure that places anti-inflammatory steroid medicine into the epidural space around irritated spinal nerve roots to ease neck, back, arm, or leg pain. It usually brings temporary relief lasting days to months, helps about half of people, and is generally limited to two or three injections per year. [1]
What the research says
Benefit for sciatica is real but modest in the short term. A review of 25 placebo-controlled trials (2,470 people) found steroid injections lowered leg pain by about 5 points and disability by about 4 points on 0–100 scales between 2 weeks and 3 months — smaller than the 10-point change most patients notice. (Oliveira et al., Cochrane Database Syst Rev, 2020) [2]
Infection after an ESI is uncommon. A systematic review of interventional spine procedures counted 219 infections in 174,431 epidural steroid injections, a rate of 0.13% — roughly 1 in 800. (Santiago et al., Pain Physician, 2021) [3]
Timing matters if spine surgery may follow. In Medicare patients over 65, lumbar decompression within 1 month of a lumbar ESI carried 3.2 times the odds of a 90-day infection compared with matched controls; with a gap of more than 3 months, the difference was no longer significant. (Yang et al., Spine J, 2016) [4]
Key takeaways
An ESI targets pain caused by inflamed spinal nerve roots, such as sciatica from a herniated disk or spinal stenosis. [1]
Relief usually starts 2 to 7 days after the injection; pain may get worse for 2 to 3 days first. [1]
About 50% of people get pain relief, which typically lasts weeks to months and rarely up to a year. [1]
Most doctors allow 2 to 3 injections per year because frequent steroid doses can weaken spinal bones and nearby muscles. [1]
An ESI eases pain but rarely cures the cause, so it usually works alongside physical therapy and other care. [1]
How does an epidural steroid injection work?
An epidural steroid injection works by bathing an inflamed spinal nerve root in steroid medicine, which reduces swelling and pressure on the nerve and gives it time to heal. [1]
Your spinal cord carries signals between your brain and the rest of your body. It sits inside a column of small bones called vertebrae, with cushioning disks between them. [1]
Around the spinal cord is the epidural space — a sleeve-like layer holding fat, blood vessels, connective tissue, the dural sac, and spinal nerves. [1]
When a nerve root branching off the spinal cord gets pinched or inflamed — for example, by a herniated disk — pain can travel into the arm, buttock, or leg. The location of the pain depends on which nerve is affected. [1]
Most of the time the relief is temporary, but some people have long-term or even permanent relief. An ESI can also help your doctor pinpoint which nerve is causing the pain. [1]
Important: An ESI is not the same as the epidural used during labor or surgery. Those epidurals use local anesthetic to numb part of the body, while an ESI uses a steroid to calm inflammation. [1]
What conditions can an epidural steroid injection treat?
An epidural steroid injection treats chronic pain from irritated spinal nerve roots, most often low back pain that spreads into the buttocks or legs, or neck pain that spreads into the arms. [1]
Condition | How it causes nerve pain |
Disk material presses on and pinches a nerve root | |
Spaces inside the spine narrow and crowd the nerves | |
Failed back surgery syndrome | Pain continues after back or spine surgery that did not succeed |
Vertebral bone spurs (osteophytes) | Bony growths irritate nearby nerves |
A curved spine irritates a nerve root | |
Spondylolysis | A problem in part of the vertebra irritates nerves |
Other spinal injuries | Damage to nerves, vertebrae, or surrounding tissue |
Doctors usually suggest an ESI only after pain has not improved with physical therapy, medicines, or other nonsurgical treatments. [1] If your pain runs down one leg, our sciatica guide and radiculopathy guide explain the underlying causes in more detail.
ESIs are widely used: roughly 9 million are performed each year in the United States. [1]
What are the different types of epidural steroid injection?
Epidural steroid injections are grouped in two ways: by the part of the spine treated (cervical, thoracic, or lumbar) and by the route the needle takes to reach the epidural space (interlaminar, transforaminal, or caudal). [1]
By spine region
Type | Needle entry | Typical reason |
Cervical (neck) | Just to the side of the spine in the neck | Neck pain spreading into the arms from a herniated disk, bone spur, or stenosis |
Thoracic (upper/middle back) | Just to the side of the spine in the upper or middle back | Thoracic disk herniation or thoracic spinal stenosis |
Lumbar (low back) | Just to the side of the spine in the low back | Low back and leg pain from a herniated disk, degenerative disk disease, or stenosis |
By needle route
Approach | Needle path |
Interlaminar | Between two laminae — the flat bony plates at the back of each vertebra that form the outer wall of the spinal canal |
Transforaminal | Through a foramen — the opening where a nerve root exits the spine |
Caudal | Through the sacral hiatus, near the bottom of the sacrum just above the tailbone, to reach the lowest spinal nerves |
For a closer look at the lowest route, see our guide to the caudal epidural steroid injection.
Who performs an epidural steroid injection?
An epidural steroid injection is performed by a doctor with specialized training, because the technique is very precise. [1]
These specialists commonly perform ESIs:
Physiatrists (physical medicine and rehabilitation doctors)
Radiologists
Anesthesiologists
Neurologists
Surgeons
How do you prepare for an epidural steroid injection?
Preparing for an epidural steroid injection starts with telling your doctor about every medicine you take — including herbs, supplements, and over-the-counter products — and whether you are or might be pregnant. [1]
Your doctor may also:
Ask you to stop eating and drinking for a set time beforehand.
Adjust some medicines, especially blood thinners.
Order an MRI or CT scan of your spine to find the exact area to treat.
Ask you to bring someone to drive you home if you will receive a sedative. [1]
Questions worth asking your doctor:
How often do you perform ESIs?
How should I prepare?
What are the risks for me?
What will the injection feel like?
How long is the relief likely to last? [1]
What happens during an epidural steroid injection procedure?
An epidural steroid injection procedure is done in a hospital or outpatient clinic and follows a short series of steps. [1]
Positioning: You change into a gown and lie face down on a padded table.
Cleaning: The skin over the injection site is cleaned thoroughly to lower the risk of infection.
Numbing: A small needle delivers local anesthetic so the larger epidural needle hurts less. You may also get a sedative to help you relax.
Guidance: Using live X-ray imaging (fluoroscopy), the doctor guides the needle into the right position. Staying still is important.
Contrast dye: Once the needle is in the epidural space, a contrast dye may be injected so the target area shows clearly on screen and the medicine reaches the inflamed nerve.
Medicine: The steroid is injected slowly. Some doctors mix it with a local anesthetic.
Finishing: Pressure is applied to stop bleeding, the area is cleaned, and a bandage goes on. You rest for a few minutes to an hour so the team can watch for any reaction before you go home. [1]
What does an epidural steroid injection feel like?
An epidural steroid injection usually feels like a brief pinch when the numbing medicine goes in, and many people feel little else during the injection itself. [1]
Some people notice:
Pressure
Tingling
A burning sensation
Brief pain
Any discomfort usually fades once the injection ends. Tell your doctor right away if you feel intense, sharp pain during or after the procedure. [1]
What happens after an epidural steroid injection?
After an epidural steroid injection, soreness where the needle went in is normal and usually lasts only a few hours. Your doctor may advise taking it easy for the rest of the day. [1]
Your pain may feel worse for 2 to 3 days before it starts to improve. The steroid generally begins working within 2 to 7 days. [1]
How long does an epidural steroid injection last?
An epidural steroid injection usually relieves pain for weeks to months, and rarely for as long as a year, depending largely on what is causing the pain. [1]
Question | Answer |
When does it start working? | Within 2 to 7 days [1] |
How long does relief last? | Weeks to months; rarely up to a year [1] |
How many people get relief? | About 50% [1] |
How many injections per year? | Usually no more than 2 to 3 [1] |
Does it cure the problem? | In most cases, no — other treatments are usually needed for lasting relief [1] |
People living with chronic pain who receive ESIs often need other therapies alongside them to keep pain under control. [1]
What are the benefits of an epidural steroid injection?
The main benefit of an epidural steroid injection is pain relief — usually temporary, sometimes long-term — that makes daily activities easier. [1]
Other benefits include:
Better quality of life and more freedom to move without pain limiting you.
Diagnostic information about where the pain comes from, which helps when there is more than one possible cause.
Less need for more invasive pain procedures. [1]
What are the side effects of an epidural steroid injection?
The most common side effect of an epidural steroid injection is a short-lived increase in pain before the steroid starts working. [1]
Side effect | What to know |
Temporary pain flare | Common before the medicine takes effect |
Tenderness or bruising | At the injection site |
Low-level radiation | From fluoroscopy; X-rays can harm a developing baby, so always tell your doctor if you may be pregnant |
High blood sugar | Likely in people with diabetes and can last hours or days — see our hyperglycemia guide |
Raised blood and eye pressure | Possible, temporarily, in people with glaucoma |
[1]
What are the risks of an epidural steroid injection?
Epidural steroid injections are generally safe, but rare complications can happen. The FDA requires a warning that injecting steroids into the epidural space can rarely cause serious problems such as loss of vision, stroke, paralysis and death, and these steroids are not FDA-approved for this use. [1]
Rare risk | Details |
Can cause lightheadedness | |
Severe headache | From a leak of spinal fluid; affects fewer than 1% of people |
Infection | Including epidural abscess, discitis, osteomyelitis, or meningitis |
Medicine reaction | Such as hot flashes or a rash |
Bleeding | If a blood vessel is damaged, a hematoma or blood clot can form |
Nerve damage | At the injection site |
Bladder or bowel control problems | Usually temporary; a urinary catheter may be needed |
Weaker bones or muscles | From frequent injections or high steroid doses — the reason for the 2-to-3-per-year limit |
[1]
Can an epidural steroid injection cause long-term problems?
An epidural steroid injection can, very rarely, cause lasting harm, including:
Permanent nerve problems from damage to the spinal cord or a nerve root
Chronic pain from that same damage
Permanent paralysis from a blood collection pressing on the spinal cord [1]
If spine surgery may follow, ask your surgeon about timing: in one large study, operating within 3 months of a lumbar ESI was linked with a higher infection rate. [4]
When should you call a doctor after an epidural steroid injection?
You should contact your doctor or go to the nearest hospital promptly if any of these warning signs appear after an epidural steroid injection. [1]
Warning sign | What it may mean |
Severe headache when sitting or standing that eases when lying down | Possible puncture of the dura (spinal fluid leak) |
Fever | Possible infection |
Reduced or lost bladder or bowel control | Possible nerve problem — seek urgent care |
Numbness or weakness in the legs | Possible nerve injury |
[1]
Epidural steroid injection at a glance
Feature | Details |
What it is | Steroid medicine injected into the epidural space around spinal nerves |
Main use | Chronic neck, back, arm, or leg pain from inflamed nerve roots |
Where it is done | Hospital or outpatient clinic |
Imaging | Fluoroscopy (live X-ray), often with contrast dye |
Time to work | 2 to 7 days |
Relief | About 50% of people; weeks to months |
Yearly limit | Usually 2 to 3 injections |
Common side effects | Temporary pain flare, bruising, high blood sugar in diabetes |
Rare risks | Spinal fluid headache (<1%), infection, bleeding, nerve damage |
[1]
Conclusion
An epidural steroid injection is a widely used, generally safe way to calm pain from inflamed spinal nerves when physical therapy and medicines have not been enough. [1] Around half of people get relief, usually lasting weeks to months, but the injection rarely fixes the underlying problem — so it works best as one part of a broader plan. [1] Research supports a modest short-term benefit for sciatica, with serious complications such as infection being uncommon. [2][3]
If you are considering an ESI, talk through your expected benefit, your medicines, and any plans for surgery with your doctor, and learn the warning signs before you go home.
Keep learning: Read our guides to sciatica, herniated disks, and spinal stenosis, and bookmark our health library for clear, physician-reviewed health information.
FAQ
What is an epidural steroid injection used for?
An epidural steroid injection is used to ease chronic pain caused by inflamed spinal nerve roots, such as neck pain spreading to the arms or low back pain spreading to the legs. Common causes include herniated disks, spinal stenosis, and bone spurs. [1]
Does an epidural steroid injection hurt?
An epidural steroid injection usually causes only a brief pinch from the numbing medicine. You may feel pressure, tingling, burning, or brief pain during the injection, which typically fades once it is finished. [1]
How long does it take for an epidural steroid injection to work?
An epidural steroid injection usually starts working within 2 to 7 days. Pain can feel worse for the first 2 to 3 days before it improves. [1]
How long does pain relief from an epidural steroid injection last?
Pain relief from an epidural steroid injection typically lasts weeks to months and rarely up to a year. How long it lasts depends mostly on the cause of the pain. [1]
How many epidural steroid injections can you have in a year?
Most doctors limit epidural steroid injections to 2 to 3 per year. Frequent injections or high steroid doses can weaken the spinal bones and nearby muscles. [1]
What are the side effects of an epidural steroid injection?
The most common side effects of an epidural steroid injection are a temporary pain flare and tenderness or bruising at the injection site. People with diabetes may have high blood sugar for hours or days, and people with glaucoma may have a temporary rise in eye pressure. [1]
Is an epidural steroid injection the same as an epidural for labor?
No, an epidural steroid injection is not the same as a labor epidural. A labor epidural uses local anesthetic to numb part of the body, while an epidural steroid injection uses a steroid to reduce nerve inflammation. [1]
When should I seek emergency care after an epidural steroid injection?
Seek care promptly after an epidural steroid injection if you develop a fever, leg numbness or weakness, loss of bladder or bowel control, or a severe headache when upright that eases when lying down. These can signal infection, nerve injury, or a spinal fluid leak. [1]
How should I prepare for an epidural steroid injection?
Tell your provider about all your medicines, especially blood thinners, because you may need to pause some first. Do not stop any medicine without instructions, and arrange for someone to drive you home.
Can I drive home after an epidural steroid injection?
Most people are advised not to drive right after an epidural steroid injection, especially if they received sedation. Plan for someone else to take you home.
Related Reading
Cervical Epidural Steroid Injection: Uses, Procedure and Results explains cervical epidural steroid injections.
Lumbar Epidural Steroid Injection: Uses, Procedure and Results explains epidural steroid injections for low back pain.
References
Cleveland Clinic. Epidural Steroid Injection (ESI): What It Is, Benefits, Risks & Results. Cleveland Clinic. Last updated December 29, 2021. https://my.clevelandclinic.org/health/treatments/22301-epidural-steroid-injection-esi
Oliveira CB, Maher CG, Ferreira ML, et al. Epidural corticosteroid injections for lumbosacral radicular pain. Cochrane Database Syst Rev. 2020;4(4):CD013577. PMID 32271952. https://doi.org/10.1002/14651858.CD013577
Santiago K, Cheng J, Jivanelli B, et al. Infections Following Interventional Spine Procedures: A Systematic Review. Pain Physician. 2021;24(2):101-116. PMID 33740341. https://pubmed.ncbi.nlm.nih.gov/33740341/
Yang S, Werner BC, Cancienne JM, et al. Preoperative epidural injections are associated with increased risk of infection after single-level lumbar decompression. Spine J. 2016;16(2):191-196. PMID 26235469. https://doi.org/10.1016/j.spinee.2015.07.439
Further reading (external):
National Library of Medicine (US). Epidural injections for back pain. MedlinePlus Medical Encyclopedia. Last updated June 4, 2025. https://medlineplus.gov/ency/article/007485.htm
Radiological Society of North America; American College of Radiology. Epidural Injections. RadiologyInfo.org. Last updated March 11, 2024. https://www.radiologyinfo.org/en/info/epidural
Medical disclaimer
This article is for general educational purposes only and does not replace professional medical advice, diagnosis, or treatment. Always talk with a qualified healthcare provider about your symptoms and before starting or changing any treatment. If you think you are having a medical emergency, call your local emergency number right away.
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