Cortisone is a naturally occurring corticosteroid hormone produced by the body’s adrenal glands. Corticosteroids are a class of medications that are related to natural cortisone and can help to relieve the pain and swelling from arthritis.
In rheumatology, corticosteroids may be called steroids (for short) and sometimes cortisone. Corticosteroids are very different from the risky anabolic steroids that cheating athletes and bodybuilders take to artificially boost testosterone levels and enhance athletic performance.
Examples of corticosteroids include methylprednisolone (depomedrol), triamcinolone acetonide (kenalog), triamcinolone hexacetonide (aristospan), and betamethasone (celestone).
Steroid injections can be a valuable treatment for many types of arthritic conditions including inflammatory types of arthritis such as rheumatoid arthritis, psoriatic arthritis, gout, and lupus. People with osteoarthritis and conditions like tendonitis, bursitis, and tendon nodules can also benefit from steroid injections.
Taking Cortisone Injection
How Cortisone is Injected
Steroids are injected locally: either directly into the joints (intra-articular) or around the joints (peri-articular) or tendons being treated.
Steroid injections reduce inflammation (heat, redness, swelling, and pain) in and around the injected joint. The dosage varies depending on the kind of corticosteroid.
Most injections are safely and routinely performed in a physician’s office. For joints in the spine or hip, injections are usually given by a radiologist with help from an x-ray or ultrasound.
A local anesthetic (lidocaine) is sometimes given before the injection, or it can be mixed with the steroid, to give immediate relief.
How Long Cortisone Lasts
Most injections typically take 24 to 72 hours to take full effect. If local anesthetic was given with the steroid injection, patients may feel improvement relatively quickly. The duration of improvement varies. Some patients report months of relief whereas others find only a few days of relief.
If possible, it is best to rest the joint or tendon for 24 to 48 hours after the injection. This may make the injection work better and last longer.
Patient Response and Repeat Treatments
In general, if a patient is going to respond to a steroid injection, they tend to respond after the first injection.
People who have gained no symptom relief or functional benefit from two injections should probably not continue with repeat injections because the likelihood of improvement is small.
If a significant benefit is achieved after the first injection, then an argument can be made for a repeat injection.
There is some controversy in the medical community that too many injections may weaken tendons, ligaments, and accelerate the loss of cartilage. Other research has found that injections can slow joint damage and help preserve the joint. A reasonable approach is to limit the frequency of injections to 3-4 for a single joint per year.
Important Tests and Risks
The vast majority of steroid injections go smoothly and there are no serious side effects.
Steroid Flare and Infection Risk
A small and very rare risk is that the injected joint becomes infected (1 in 15,000).
Patients who experience a very painful, red, or swollen joint after injection should seek medical attention immediately.
Thankfully, the most common cause of these symptoms is not a concerning infection but a reaction to the injected steroid called steroid flare that occurs in 2-5% of patients.
A steroid flare usually begins 6 to 12 hours after the injection and can last for 2 to 3 days.
Regardless of the cause, it is important for patients with symptoms of infection to see a doctor because infections require immediate treatment.
Rise in Blood Sugars in Diabetics
In patients with diabetes, a steroid injection can sometimes cause a rise in blood sugars.
These patients should make sure to test their blood sugars for a few days after the injection.
Stop 3 Months Before Surgery on a Joint
Joint injections are not usually recommended within 3-months of surgery on a joint because this can increase the risk of infection.
How Steroid Injection Works
Cortisone is a naturally occurring corticosteroid hormone produced by the body’s adrenal glands. Corticosteroids are a class of medications that are related to natural cortisone that are designed to work in a similar way inside the body.
Cortisone affects many parts of the body including the immune system. It helps lower levels of prostaglandins, hormone-like lipids that play a role in causing inflammation (heat, redness, swelling, and pain), and it can soften the response of the immune system’s T-cells and B-cells, which are types of white blood cells.
When delivered directly into a joint or tendon impacted by arthritis, corticosteroids mimic the effect of natural cortisone and reduce inflammation. Its relatively fast action compared to many other treatments helps make cortisone injections a useful tool in treating arthritis.
Cortisone injections are usually fairly well tolerated by patients. The biggest concern is often the very rare possibility (1 in 15,000 to 1 in 20,000) of infection. Patients should see a doctor immediately if they get a fever after an injection, or if an injected area becomes very painful, red, or swollen.
Possible side-effects include:
- Infection – rarely a joint can become infected after injection. Steroids in general can also make it harder the body to fight infections. Patients should call their doctor if they have a fever or think they have an infection.
- Injury to the joint or tendon – A steroid injection can rarely cause injury to a joint or a tendon. Patients are encouraged to discuss this risk with their doctor.
- Tendon rupture – If a steroid injection is performed around a tendon, a rare risk is rupture of the tendon. This is more common around tendons that are already weak or partially ruptured, and more common in those in the legs. If a steroid injection is given around a tendon it is best to rest and immobilize the area for 24-48 hours.
- Post injection pain – Some patients may experience increased pain and discomfort in the injected joint. It is thought to be caused by a reaction to the steroid or perhaps bleeding into the joint. Post-injection pain can be treated with ice packs or with pain medications including NSAIDs.
- Flushing – After an injection some patients feel “flushed”. This usually isn’t serious but patients should tell their doctor if this happens.
- Rise in blood sugars – A steroid injection can sometimes cause a rise in blood sugars in patients who have diabetes. These patients should make sure to test your blood sugars for a few days after the injection.
- Skin changes – A steroid injection can rarely cause changes to the skin:
- Loss of pigment – Steroid injections can cause an area of the skin to lose pigment (turn white; called vitiligo). This is more common in darker skinned people.
- Loss of fat layer – Steroids can also cause loss of the fat layer just below the skin (called fat necrosis) that may cause a depression or unusual appearance, and may cause the skin to turn a purple color. It is not serious but it can look funny. Over time the fat usually returns. When this happens, usually the steroid injection worked really well.
- Rash – Steroid injections can sometimes cause a rash on the arms called ecchymosis.
- Sleep trouble & increased energy – A steroid injection can sometimes make patients feel full of energy. This can sometimes make it difficult to sleep.
Patients should talk to their doctor if they are concerned about any side effects.
Who Should NOT Take Cortisone
Patients that should NOT take Cortisone include:
- Patients who have had a previous allergic reaction to corticosteroids or an ingredient in the shot
- Patients who have not responded well to Cortisone treatment
- Possibly patients with an active infection or a systemic fungal infection
- Possible patients with a blood clotting disorder (such as haemophilia).
Patients who become pregnant while receiving Cortisone therapy should tell their doctor. It is generally advisable to avoid all medications during pregnancy and while trying to become pregnant. However, local steroid injections are believed to be one of the safer treatments for arthritis during pregnancy.
When to Call a Doctor
Patients taking Coritisone should call their doctor if they feel unwell after receiving an injection, or if they are concerned about any side effects.
Other reasons to call a doctor after receiving a corticosteroid injection include:
- Severe pain in the area injected
- Fever or possible infection
- Skin changes or loss of pigment
Watch Dr. Andy Thompson, a Canadian rheumatologist, introduce Cortisone Injections in this short video: