Diabetes does not automatically rule out a joint injection. It does change the questions that should be answered before treatment: which injection is being considered, how well your diabetes is controlled, what monitoring you need and who will help if glucose rises. A PRP appointment and a corticosteroid injection are not interchangeable procedures, even when both are offered for joint pain.
Start with the diagnosis, not the injection menu
A painful knee or shoulder needs an assessment of its cause. Osteoarthritis, a tendon problem, inflammatory arthritis and infection do not share one treatment pathway. Diabetes is part of that assessment, alongside the examination, previous treatment and relevant imaging. Choosing an injection first can distract from the condition that actually needs treating.
An acutely hot, swollen joint, particularly with fever or feeling unwell, needs urgent medical assessment rather than a routine PRP booking. Do not assume that a sudden deterioration is simply an arthritis flare. If you are seriously unwell, seek emergency care appropriate to your location.
Explore the clinic's assessment and treatment information. For a planned review, bring your diagnosis if known, imaging reports, details of previous injections and how long any benefit lasted. A good consultation should explain whether an injection has a reasonable role at all, including alternatives such as rehabilitation and the reasons for delaying or declining treatment.
Why steroid injections need a glucose plan
Corticosteroid injected into a joint can temporarily increase blood glucose. EULAR's recommendations advise informing people with diabetes about this risk, especially when control is suboptimal, and monitoring glucose particularly during the first to third day after an intra-articular glucocorticoid injection. AAOS also notes that a small amount of injected steroid can enter the bloodstream and temporarily raise glucose.
That recommendation is not a promise that every rise ends after three days. The monitoring plan should fit your usual readings, diabetes treatment, previous response to steroids and the procedure proposed. Ask what to measure, how often, for how long and which result or symptom should trigger a call. If you use a sensor, discuss how its readings fit your existing diabetes plan.
Do not change insulin or tablets yourself in anticipation of an injection. If a temporary adjustment may be needed, agree it with the clinician responsible for your diabetes. Before the appointment, confirm who you can contact outside the injection clinic's opening hours and use your established sick-day advice when relevant.
Is PRP the same as a steroid injection?
No. Platelet-rich plasma is prepared from a sample of your own blood and is different from a corticosteroid. It should not be described as a steroid injection, and the steroid-specific glucose warning should not be presented as proof that PRP has the same effect.
The opposite conclusion would also be wrong: being different from a steroid does not establish that PRP is risk-free, more effective or the best option for every person with diabetes. Evidence for PRP depends on the condition, treatment protocol and outcomes studied. An injection cannot be judged on a general label such as 'natural'.
Ask exactly what will be injected, whether any other medicine is planned, what evidence applies to your diagnosis and how your health changes the balance of benefit and risk. If the proposal changes on the day, the discussion and consent need to reflect the actual treatment, not the one you expected from a website.
Do I need an HbA1c result before treatment?
A recent HbA1c and your usual glucose pattern can help the clinician understand control. Bring the result and its date if available, along with any recent episodes of low glucose, very high glucose, illness or changes in treatment. HbA1c describes a longer-term pattern; it does not replace discussion of what has happened this week.
This guide does not set a universal HbA1c cut-off for an injection. EULAR's recommendation is to inform and monitor patients, particularly those with suboptimal control, not to use a website threshold as a substitute for an individual decision. The clinician may need updated information, input from your diabetes team or a period of improved control before proceeding.
If the clinic asks for a new test, ask why it is needed, who will interpret it and whether it changes the timing or choice of treatment. A result should support a decision, not become an unexplained hurdle or a guarantee of safety once a number is reached.
What else should the clinic know?
Bring a complete medicine list, including diabetes medicines, blood-thinning medicines, steroids and supplements. Include allergies, recent infection, antibiotics, wounds near the proposed injection site and previous procedure complications. Tell the clinician if you have had a joint replacement or have surgery planned, because this may change the appropriate pathway.
Do not stop a prescribed blood thinner or another medicine solely because you have read general advice about injections. The prescribing clinician and procedural clinician should agree any change. Equally, do not assume an injection is suitable because you have had one safely before: the joint, product and your health may now be different.
Ask whether you should eat and take your usual diabetes medicines before the visit. Instructions depend on the actual procedure and your treatment. Do not fast unless specifically instructed, and make sure any preparation advice accounts for the risk of hypoglycaemia.
Agree the aftercare before giving consent
Before treatment, you should understand the likely discomfort, activity advice, warning symptoms and follow-up arrangements. EULAR recommends avoiding overuse of an injected joint for 24 hours while discouraging immobilisation, but your specific procedure may need a different rehabilitation plan. Get the plan for the treatment you actually receive.
Ask how to distinguish expected soreness from a problem that needs review. Increasing severe pain, a hot or markedly swollen joint, fever or feeling unwell after an injection need prompt medical advice. A glucose plan should state when to contact your diabetes team, the injection clinic or urgent services rather than leaving you to interpret an isolated reading alone.
Contact The London PRP Clinic to discuss a London assessment and explain that you have diabetes before arranging a procedure. Confirm the diagnosis review, proposed treatment, separate testing costs and follow-up arrangements. An assessment is not a promise that PRP or any other injection will be offered.
Questions worth taking to the appointment
What is causing the pain, and why is this injection appropriate? What will be injected? What evidence applies to someone with my diagnosis and health history? Do you need a current HbA1c or input from my diabetes team? Who owns the glucose and aftercare plan? What would make you postpone treatment?
Clear answers are more useful than a blanket reassurance that diabetes is 'fine' or that one injection is always safer. The aim is an informed, individual decision with a workable plan afterwards.
Evidence and scope
General adult information, not personal diabetes or prescribing advice. Evidence checked 6 November 2026. The EULAR recommendations concern intra-articular therapies; their glucose recommendation is specifically about glucocorticoid injection. It is not a trial proving PRP's effectiveness or superiority in diabetes.
EULAR: recommendations for intra-articular therapies, including diabetes and glucose monitoring.