Corticosteroid Injections: Which Steroid, and How Often

Written by Gisele J. Girault, MD

Updated September 2026 ·9 min read

Corticosteroid is the most frequently injected drug in joint and extremity practice, and most of what patients ask about it — how often, what it does to blood sugar, why it hurt more afterwards — has clear answers that are rarely given in advance.

This guide covers them, following the teaching of Gisele J. Girault, MD.

Glucocorticoid, not mineralocorticoid

Two classes of corticosteroid exist and only one belongs in a joint.

Glucocorticoids are injected — hydrocortisone, prednisone, methylprednisolone, triamcinolone and betamethasone — because, as Girault puts it, they have “greater anti-inflammatory properties, which is why we want to use them in our injections to begin with.”

Mineralocorticoids — fludrocortisone and cortisone — are not, because their effects are predominantly on fluid and electrolyte balance rather than inflammation.

Cloudy or clear: the test you can do by eye

Within the glucocorticoids the practical distinction is particulate versus non-particulate, and Girault teaches a check that requires no reference material: hold the vial up and look at it.

Cloudy means particulate. Triamcinolone and methylprednisolone are cloudy, and that cloudiness is, in her words, “undissolved particles floating in a suspension.” They are depot preparations and last longer.

Clear means non-particulate. Dexamethasone is clear.

The distinction matters most in the spine, where particles “can get into small blood vessels” — which is why she uses dexamethasone for spinal work specifically. She adds a supply note worth planning around: dexamethasone is in high demand and is the cheapest option, so it goes out of stock regularly. She keeps a second steroid on hand as standard.

Steroid flare: tell the patient before they leave

The single most useful thing to say at the end of the appointment.

Increased pain over the 24 to 48 hours following injection happens in roughly one in ten injections. Girault warns every patient about it: it is a steroid flare, it settles over the next day or two, and there is “no need for them to run to the emergency room” — though they should feel free to ring the office.

Framed in advance, it is an expected event. Encountered without warning, it reads as a complication, and it generates an out-of-hours call or an unnecessary emergency attendance.

The systemic effects of an injected steroid

An injection is local, but the drug is absorbed. Girault lists the systemic effects as facial flushing, raised blood sugar, raised blood pressure, insomnia, increased appetite, mood swings and adrenal suppression.

Of those, the two she watches are raised blood sugar and adrenal suppression. The rest are unpleasant and transient; those two have consequences.

Facial flushing is common enough to be worth mentioning at consent simply so it is not alarming, and insomnia the night after is frequent.

Diabetes: substitute rather than cancel

Diabetic patients are among the largest groups in a pain practice, and steroid raises glucose.

Girault's approach before injecting steroid is to confirm that haemoglobin A1c and fasting glucose are under good control. Where they are not, the useful part is what she does next: rather than declining the procedure, she performs several of these injections “with local anaesthetic alone, leaving out the steroid, because steroids can increase blood sugars.”

That reframes the steroid as one component of the injection rather than the whole of it. A patient with poor glycaemic control can still have a diagnostic block, a trigger point injection or a local anaesthetic joint injection.

And it is worth noting that trigger point injections do not routinely contain steroid in any case — Girault uses steroid for most injections “with the exception of trigger point injections.”

The other groups that change the plan

Girault identifies five populations that most often require modification: diabetics, patients on antibiotics, patients on anticoagulants, patients already taking oral steroids, and obese patients.

Patients already on oral steroid deserve particular thought, since the injected dose adds to an existing systemic burden and the adrenal suppression concern compounds.

Patients on antibiotics raise the question of why — an active infection is a reason to defer, not to proceed carefully.

Anticoagulated patients are a different calculus for superficial compressible targets than for deep or neuraxial ones.

How often injections can be repeated

There is no single legislated interval, and most practice works to roughly three or four injections to the same site in a year, spaced by at least several weeks.

The limiting factors are cumulative systemic exposure — the adrenal suppression and glucose effects above — and, with repeated steroid around degenerate tendon, the tissue itself.

Which points at the more useful question. A joint or tendon needing a fourth injection in a year is telling you the underlying problem has not been addressed. That is an argument for reconsidering the diagnosis, the rehabilitation, or the mechanical driver — not for a fourth injection.

Where steroid is the wrong drug entirely

Girault distinguishes tendonitis from tendinosis, and the distinction changes the drug.

Tendonitis is inflammatory and responds to an anti-inflammatory. Tendinosis is degenerative — disorganised collagen without much inflammation — so a steroid is acting on a process that is not the dominant problem.

That is where the regenerative alternatives earn their conversation, and where the published evidence for them is strongest: a single PRP injection outperformed corticosteroid in lateral epicondylitis with benefit maintained at two-year follow-up. The evidence is set out in regenerative pain medicine.

What to ask before a steroid injection

1. Which steroid, and is it particulate or non-particulate?
2. If I have diabetes, can this be done without the steroid, and what would that cost me in effect?
3. What should I expect in the first 48 hours, and what would be abnormal?
4. How many of these can I have, and what happens when we reach that?
5. Is the problem inflammatory or degenerative — and if degenerative, is a steroid the right drug?