What is an epidural corticosteroid injection?

In the simplest of terms, an epidural corticosteroid (steroid) injection is a way to deliver pain medicine quickly into the body with a syringe.

The medicine is injected into the epidural area. This is a fat-filled area that covers the spinal cord to protect it and the surrounding nerves from damage.

Sometimes pain relief is short term. Other times the benefits continue for some time.

Why might I need an epidural steroid injection?

If you have intense, difficult-to-treat pain in your legs or arms from inflamed spinal nerves, then an epidural steroid injection might give you quick relief. Often, nerve passages from the spine to your arms or legs become narrowed, causing this pain. This narrowing can cause inflammation of the spinal nerves.

A number of conditions may add to this narrowing, including:

• Herniated disks
• "Slipped" vertebrae
• Joint cysts
• Bone spurs
• Thickening ligaments in the spine because of spinal arthritis

Injected steroids reduce inflammation and opens up these passages to provides pain relief.

What are the risks of an epidural steroid injection?

An epidural steroid injection generally causes no problems. If you do have side effects, they may include:

• "Steroid flush," or flushing of the face and chest, with warmth and an increase in temperature for several days
• Sleeping problems
• Anxiety
• Menstrual changes
• Water retention
• In rare instances, pain that actually increases for several days after the procedure

Serious complications are rare but can include:

• Allergic reaction
• Bleeding
• Nerve damage
• Infection
• Paralysis

How do I get ready for an epidural steroid injection?

• An epidural steroid injection is generally an outpatient procedure. You may be asked to change into a surgical gown to make the injection process easier.
• You may want to ask for a mild sedative, but most people receive just local anesthetic.
• If you have diabetes, an allergy to contrast dye, or certain other medical conditions, you'll want to discuss any concerns with your healthcare provider before getting the procedure.

Based on your medical condition, your healthcare provider may request other specific steps.

What happens during an epidural steroid injection procedure?

An epidural steroid injection is a simple procedure:

1. Your healthcare provider will use an X-ray machine showing moving images on a screen to guide the needle as he or she makes the injection and ensures that the needle is in the correct location.
2. Contrast dye is injected at the site to make sure that the medicine will be sent to the exact place it needs to go.
3. The healthcare provider will inject the steroid medicine itself, often along with a local anesthetic to help with pain relief.

What happens after an epidural corticosteroid injection procedure?

Once the procedure is done, you can return home. Usually, you'll be able to return to normal activities on the next day. The steroids usually begin working within 1 to 3 days. In some cases, you might need up to a week to feel the benefits.

Many people get several months of improvement of pain and function from the injections. If the injection is effective, it can be repeated. If you have any side effects, be sure to contact your healthcare provider.

If you don't have pain relief, talk with your healthcare provider. This may be a sign that the pain is coming from some place other than the spinal nerves. 

Next steps

Before you agree to the test or the procedure make sure you know:

• The name of the test or procedure
• The reason you are having the test or procedure
• What results to expect and what they mean
• The risks and benefits of the test or procedure
• What the possible side effects or complications are
• When and where you are to have the test or procedure
• Who will do the test or procedure and what that person’s qualifications are
• What would happen if you did not have the test or procedure
• Any alternative tests or procedures to think about
• When and how will you get the results
• Who to call after the test or procedure if you have questions or problems
• How much will you have to pay for the test or procedure