After a cortisone injection, the most important thing to avoid is stressing the treated joint for at least 24 to 48 hours. That means no running, heavy lifting, or high-impact exercise during that window. But physical activity isn’t the only concern. How you care for the injection site, what you put on it, and even how you monitor your body in the days that follow all matter for getting the most out of your shot.
Don’t Exercise the Joint for 1 to 2 Days
The first 24 hours after your injection should be spent resting the affected joint. This rest period serves two purposes: it gives the medication time to absorb into the tissue, and it lets you monitor for any adverse reactions. Jumping back into activity too soon may actually undermine the injection’s benefits.
Animal studies offer a cautionary picture. Rats that ran daily after receiving joint injections developed significantly more cartilage damage than rats that either ran without injections or received injections without running. While human data on this specific question is limited, the pattern suggests that loading a freshly injected joint with impact forces is not a good idea.
If you received a lower-extremity injection (knee, ankle, hip), start reintroducing activity after 24 to 48 hours with low-impact options like a stationary bike, an elliptical, or bodyweight exercises. From there, ramp up gradually based on how the joint feels. For professional cyclists, the international governing body mandates a full 8 days of rest and no competition after a cortisone injection, which gives you a sense of how seriously elite sports take this recovery window.
The general recommendation for all activity levels is 1 to 2 days of relative rest, then a progressive return. “Relative rest” doesn’t mean bed rest. It means don’t do anything that heavily loads or stresses the injected area.
Don’t Soak the Injection Site
Avoid baths, hot tubs, swimming pools, and any activity that submerges the injection site in water for at least 24 hours. The tiny puncture from the needle is an open pathway for bacteria, and soaking increases infection risk. Showers are fine during this period since water runs over the site briefly rather than pooling around it.
Don’t Apply Heat
If the injection site is sore or swollen afterward, reach for ice, not heat. Apply an ice pack wrapped in a cloth for 15 to 20 minutes, two to three times a day. Never place ice directly on bare skin. Heat can increase blood flow and inflammation to an area that’s already irritated, potentially worsening swelling and discomfort during the first day or two.
What a Post-Injection Flare Feels Like
Some people experience a “cortisone flare” in the hours after their injection. The joint temporarily feels worse, not better, with increased pain and swelling at the injection site. This happens when the steroid crystals irritate the joint lining before they dissolve and start working. A flare typically peaks within the first 24 to 48 hours and resolves on its own. Ice and over-the-counter pain relief can help you ride it out.
A flare is not the same thing as an infection. The key differences matter. A cortisone flare causes soreness that stays roughly the same or gradually improves. An infection causes severe pain that comes on fast and gets worse, along with a joint that feels hot and looks swollen or discolored. Fever above 100.4°F, increasing redness that spreads outward, or any drainage from the injection site are all signs that something more serious is happening and you need medical attention quickly.
Don’t Ignore Blood Sugar Changes if You Have Diabetes
Cortisone is a steroid, and steroids raise blood sugar. If you have diabetes, this effect can be significant and may last several days after the injection. Plan to check your blood sugar four times per day (before each meal and at bedtime) for at least the first few days. Your levels may run higher than usual even with your normal medication routine, so knowing what’s happening lets you and your care team adjust if needed.
Even people without diabetes can notice mild effects like temporary flushing, a slight energy boost, or trouble sleeping the night of the injection. These are normal steroid side effects and generally pass within a day or two.
Be Cautious With Anti-Inflammatory Painkillers
The relationship between cortisone injections and common painkillers like ibuprofen or naproxen is mostly a concern before the procedure, not after, since these medications increase bleeding risk at the injection site. If you were told to stop an anti-inflammatory before your injection, ask your provider when it’s safe to resume. For joint injections in the hip, knee, or shoulder, the bleeding risk from anti-inflammatories is lower than for spinal injections, but it’s still worth confirming the timeline with whoever performed your procedure.
Driving Is Generally Safe
If you’re wondering whether you can drive yourself home, the answer for most people is yes. A study of 45 patients receiving right knee injections found no significant difference in brake response times before and after the procedure. The average braking time was essentially the same (0.83 seconds before, 0.78 seconds after), and the number of patients who failed the braking test actually decreased slightly. That said, if your injection included a local anesthetic and the joint feels numb, use common sense and wait until sensation returns before driving, especially if the injection was in your right knee or your driving shoulder.
Don’t Overdo Repeat Injections
One thing to keep in mind for the longer term: cortisone injections are not meant to be used frequently in the same joint. Current guidelines recommend spacing injections at least 3 months apart. Repeated steroid exposure can weaken cartilage, tendons, and surrounding soft tissue over time. If you find yourself needing injections more often than every few months, that’s a conversation worth having about whether a different treatment approach might serve you better.