Introduction to Steroid Injections and Post-Injection Pain
Corticosteroid injections, often called cortisone shots, are a common treatment used to reduce pain and inflammation in specific areas of the body, such as a joint or tendon [1.2.4]. They are used for conditions like osteoarthritis, tendonitis, and bursitis [1.2.4]. While many people experience significant relief, some find themselves feeling worse before they feel better. This paradoxical effect can be alarming, but it's often a known and temporary side effect.
The primary reason for this increased pain is a phenomenon known as a "cortisone flare" or "steroid flare" [1.3.2]. However, other factors, from the injection process itself to less common systemic side effects, can also contribute to feeling unwell.
The Main Culprit: The Cortisone Flare
A cortisone flare is the most frequent cause of intensified pain shortly after an injection [1.3.7]. This reaction is thought to be caused by the body's response to the corticosteroid medication itself. The steroids are formulated as slow-release crystals to provide long-term relief [1.2.5]. In some individuals, these crystals can irritate the joint's soft lining (the synovium), triggering a temporary inflammatory response before the anti-inflammatory effects kick in [1.2.5, 1.4.7].
- Symptoms: A cortisone flare typically involves intense pain, swelling, and irritation at the injection site that is more severe than the pre-injection pain [1.4.2, 1.4.7].
- Timeline: This reaction is almost always brief. It usually begins within the first 24 to 48 hours after the shot and resolves within a few days as the steroid begins to work [1.2.4, 1.3.2]. Studies show that most flares last for a mean of about two days [1.4.7].
- Incidence: Research indicates that the incidence of post-injection flare varies, with studies reporting it in anywhere from 10% to over 30% of patients, and one prospective study finding it affects about one in five people [1.6.3, 1.6.4, 1.6.5].
Other Reasons for Feeling Worse
Beyond a cortisone flare, other factors can cause discomfort:
- Needle Trauma: The physical act of the needle passing through skin, muscle, and into the joint capsule can cause localized pain and bruising [1.3.1].
- Fluid Pressure: The volume of the medication and local anesthetic injected into the small, enclosed space of a joint can temporarily increase pressure, irritating already inflamed nerves [1.2.6].
- Systemic Side Effects: The steroid medication can be absorbed into the bloodstream and cause body-wide effects, especially in older adults [1.2.1, 1.4.7]. These can include:
- Facial Flushing: A feeling of warmth and redness on the face and chest is a common reaction that typically resolves within a few days [1.3.4, 1.4.7].
- Insomnia and Anxiety: Some people experience a "hyper" or anxious sensation, similar to having too much caffeine, which can disrupt sleep for one to three days [1.2.1, 1.2.9].
- Temporary Rise in Blood Sugar: For individuals with diabetes, cortisone can cause a temporary but significant increase in blood sugar levels, which should be monitored closely [1.2.1, 1.4.3].
Comparison Table: Cortisone Flare vs. Infection
While a cortisone flare is common and temporary, a joint infection is a rare but serious complication that requires immediate medical attention [1.3.2]. It is crucial to know the difference.
| Feature | Cortisone Flare | Joint Infection |
|---|---|---|
| Onset | Within 24-48 hours after injection [1.2.4] | Can develop over several days [1.2.5, 1.4.2] |
| Symptoms | Intense pain and swelling at the joint [1.4.6]. Usually no fever. | Worsening pain, significant swelling, redness, and heat. May be accompanied by fever, chills, or pus/drainage from the site [1.2.3, 1.3.4]. |
| Duration | Self-resolves within a few days (typically 1-3) [1.2.1, 1.5.6] | Persists and worsens without treatment [1.3.2]. |
| Action | Manage at home with rest, ice, and OTC pain relievers [1.5.6]. | Contact your doctor immediately. Requires urgent medical treatment [1.3.2]. |
How to Manage Post-Injection Discomfort
If you are experiencing a typical cortisone flare, there are several steps you can take to manage the discomfort:
- Rest the Joint: Avoid strenuous activity for at least 24 to 48 hours after the injection. If the shot was in your knee or foot, try to stay off your feet as much as possible [1.2.5, 1.5.9].
- Apply Ice: Use an ice pack on the affected area for 15-20 minutes at a time, several times a day. This helps reduce inflammation and numb the pain. Do not apply ice directly to the skin; wrap it in a towel [1.5.2, 1.5.5].
- Use Pain Relievers: Over-the-counter pain medications like acetaminophen or ibuprofen can be used to manage pain, but it's always best to confirm with your doctor first [1.3.2, 1.5.5].
- Monitor Your Symptoms: Keep an eye on your symptoms. The initial flare-up of pain should begin to subside after a couple of days, followed by the intended relief from the steroid [1.2.3].
Conclusion: When to Be Concerned
Feeling worse after a steroid injection is a relatively common, albeit unpleasant, experience. In most cases, it is due to a temporary cortisone flare that resolves on its own within a few days. By resting the joint and using ice, you can effectively manage the discomfort while you wait for the powerful anti-inflammatory effects of the steroid to begin.
However, it is vital to distinguish this common reaction from the rare but serious signs of an infection. If your pain is severe and continues to worsen after 48 hours, or if you develop systemic symptoms like a fever or chills, you must contact your healthcare provider immediately [1.4.2, 1.4.3].
For more information on corticosteroid injections, you can visit the Mayo Clinic.
