General Principles of Corticosteroid Injections
When does the shot start to work?
Anesthetic pain relief for hours
Steroid takes effect in 3 to 7 days
Relief lasts 3 to 6 months (highly variable)
After injection of a corticosteroid, a typical timeline is as follows:
Within minutes to hours, the patient experiences pain relief from the anesthetic combined with the steroid.
After 12 to 48 hours the anesthetic wears off and pain returns. Steroid molecules are being absorbed into the nearby tissue and are starting to alter gene transcription, but effects are not yet apparent to the patient.
After 24 to 72 hours, measurable anti-inflammatory effects are present.
In 3 to 7 days, the patient notices decreased pain, swelling, and stiffness.
In 1 to 2 weeks, the patient enjoys the peak benefit.
After 8 to 12 weeks, the benefit begins to diminish.
Patients frequently ask, “How long will the injection last?” This is highly variable. Some patients may return a year later stating that the injection was very helpful but has begun to wear off. Others report that the injection was only helpful for a few hours, suggesting that the only relief they enjoyed was from the anesthetic.
Duration depends on several factors. Patients who will likely have a better response to the injection are those with significant synovitis or effusion, those with mild to moderate degenerative changes, and those with an acute flare of pain. Patients who will likely have a shorter response include those with severe degenerative changes resulting in deformity and mechanical symptoms.
A typical result is 3 to 6 months of pain relief in an ideal patient. When symptoms improve only marginally or return sooner than 3 to 4 months after the injection, I usually recommend looking into other treatment options.
Key Takeaways
Pain relief from the anesthetic begins lasts several hours
Pain relief from the steroid begins in 3 to 7 days and peaks at 2 weeks
Pain relief typically lasts 3 to 6 months, but this is highly variable
