Infections and arthritis medicines

The medicines that control inflammatory arthritis all work, in different ways, by quietening an immune system that has become overactive. That is true of conventional DMARDs such as methotrexate, of the biologics and JAK inhibitors, and of steroids. Quietening the immune system is exactly what makes them effective, and it is also why they raise the risk of infection: an immune system turned down against the joints is turned down, to some degree, against bacteria and viruses too. The two cannot be separated completely, and no honest guide would pretend otherwise.

What this means in daily life is easy to overstate. Most people on these medicines catch the same coughs and colds as everyone else and shake them off in much the same way. The increase in risk is real but modest for most treatments, it is one of the things your routine monitoring and reviews keep an eye on, and it sits alongside a fact that is mentioned less often: poorly controlled inflammatory disease raises the risk of infection in its own right, so good disease control is itself part of the protection.

None of this requires a restricted life. The habits that help are the ones that help everyone, applied a little more consistently:

• Wash your hands well and often, particularly before eating and after contact with anyone unwell.
• Take normal care with food: good kitchen hygiene, proper storage, and thorough cooking of meat and eggs.
• Clean and cover cuts and grazes promptly, and keep an eye on them. Redness that spreads, or a wound that becomes increasingly hot and painful, needs medical attention.
• Look after your teeth, gums and skin. Gum disease, cracked skin and athlete's foot are all entry points for infection, and all are treatable.
• Use judgement around obviously infectious illness. You do not need to avoid public life, but there is no virtue in sharing a sofa with the flu.

One exposure deserves separate mention. If you have never had chickenpox and you have close contact with chickenpox or shingles while on these medicines, contact your rheumatology team or GP promptly, because preventive treatment is sometimes considered and it is time-sensitive.

Vaccination is the other half of prevention, and one paragraph covers the essentials. Have your flu vaccine every year, keep COVID vaccination up to date as advised, and have the pneumococcal vaccine when it is offered: these are non-live vaccines, and for people on immune-suppressing treatment they are recommended, not merely permitted. The shingles vaccine belongs on the same list and is worth singling out, since shingles is exactly the kind of reactivation infection these medicines make a little more likely: the version now used in the UK is non-live, so it too is suitable during treatment, and its eligibility has recently widened to include younger adults with a severely weakened immune system. Live vaccines are different and need specialist advice before you have them, because they contain a weakened living organism; this includes some travel vaccines, such as yellow fever. Mention travel plans and vaccination questions at your reviews, because for some medicines the timing can be planned to get the best response.

Rheumatology has its own version of the sick-day rules. As a general principle, during a significant infection, one that causes a fever or needs antibiotics, DMARDs and biologic medicines are often paused until you have recovered, so that your immune system can deal with the infection at full strength. A pause made for the right reasons, at the right moment, is a routine and planned-for part of treatment, not a failure of it.

Two things stop this being a rule to apply yourself. First, it is a principle, not an instruction: whether to pause, which medicines, and for how long all depend on what you take, your condition and the infection. Second, restarting matters as much as stopping, and the right moment to restart is a judgement call too. So treat it this way: if you develop an infection with a fever, or you are prescribed antibiotics, contact your rheumatology team, tell them what is happening, and always follow your own team's advice about pausing and restarting. Minor coughs and colds without fever do not usually call for any change. And if your joints grumble while a medicine is paused, our guide to managing flares covers what helps in the meantime.

Steroid tablets such as prednisolone follow the opposite rule, and it matters enough to state plainly. If you have taken steroid tablets for more than a short time, the dose must be reduced gradually and never stopped suddenly, because the body needs time to resume making its own cortisol. Being ill does not suspend that rule; it sharpens it. During a significant illness the body normally makes more cortisol to cope, so people on longer-term steroid tablets sometimes need their dose adjusted while they are unwell, a decision for the clinicians looking after you, never one to make alone.

Keep taking your steroid tablets when you are ill, and contact your rheumatology team or the doctors treating you for advice. If you have a steroid card, carry it and show it to anyone who treats you; if you take longer-term steroids and have not been given one, ask. Our guide to steroids in rheumatology explains the background.

One of the most practical protections costs nothing: make sure every clinician who treats you knows what you take. That means your GP, any out-of-hours or A&E doctor, your dentist, and the pharmacist advising you over the counter.

It matters for two reasons. The first is that knowing you are on immune-suppressing treatment changes how seriously an infection is taken, and how quickly. The second is interactions. The clearest example: some antibiotics must not be combined with methotrexate, including trimethoprim and co-trimoxazole, so a prescriber who does not know about your methotrexate can cause real harm with an otherwise sensible prescription. Keep an up-to-date list of your medicines with you, whether a repeat prescription slip or a photo on your phone, and mention your rheumatology medicines every time, even when the appointment seems unrelated to your joints.

Most infections on these medicines stay minor. The task is not to worry about every sniffle but to recognise the few situations that need action. Seek help the same day if you have:

• A fever with shaking episodes or chills
• An infection that is worsening quickly, or leaves you feeling far more unwell than a usual cough or cold
• New confusion or unusual drowsiness, whether you notice it or someone close to you does
• A hot, swollen joint together with a fever or feeling unwell. This needs emergency assessment the same day, never a routine appointment. An infected joint (septic arthritis) can be damaged quickly and the infection can spread, and it cannot safely be told apart from a flare, gout or pseudogout without examination, usually including testing fluid from the joint. Do not wait to see whether it settles.

Sepsis is the rarest and most serious way an infection can go, when the body's response to infection starts to injure the body itself. Call 999 or go straight to A&E if you or someone with you has confusion, slurred speech or is not making sense; blue, grey, pale or blotchy skin, lips or tongue; severe breathlessness or very fast breathing; or a rash that does not fade when a glass is rolled over it.

One caution particular to rheumatology: some of these medicines, steroids among them, can blunt fever and the usual signals of infection. Feeling rapidly and unusually worse counts as a warning sign even when the thermometer looks reassuring.

A simple hierarchy covers almost every situation:

• 999 or A&E: the signs of sepsis above. This is a true emergency.
• Same-day emergency assessment, through A&E or NHS 111: a hot, swollen joint with a fever or feeling unwell.
• NHS 111 or your GP, the same day: a fever with chills, an infection that is worsening quickly, or one that is simply not improving as it should.
• Your rheumatology team: everything about the medicines themselves. Whether to pause during an infection or a course of antibiotics, steroid doses during illness, chickenpox or shingles contact, and vaccine questions all belong here. If you are under Dr Borukhson's care, you can reach the practice through the contact page.
• Your GP, routinely: infections that keep recurring, such as repeated chest, urine or skin infections. A pattern is worth reviewing, because sometimes the treatment plan can be adjusted to reduce it.

When you are unsure how urgent something is, NHS 111 exists for exactly that question, and on these medicines the right instinct is to ask.

It would be easy to read a page like this and come away more anxious than before, which would be the wrong lesson. The infection risk these medicines carry is the price of what they do, and what they do is considerable: they protect joints from damage, keep people working and active, and have transformed the outlook for inflammatory arthritis over a generation. Most people who take them get ordinary infections and recover in the ordinary way. What changes outcomes is not vigilance over every cold but clarity about a handful of situations: the fever with chills, the rapid worsening, the hot swollen joint, the steroid tablets that must never stop suddenly. Learn those, keep every prescriber informed, keep your vaccinations current, and then get on with your life. That, after all, is what the treatment is for.

I've been given antibiotics. Should I stop my methotrexate while I take them?

Ask your rheumatology team the same day rather than deciding alone. As a general principle, methotrexate and other DMARDs are often paused during a significant infection, one causing a fever or needing antibiotics, until you have recovered, but whether that applies to you depends on your medicines and your situation. There is a separate point about the antibiotic itself: some antibiotics, including trimethoprim and co-trimoxazole, must not be combined with methotrexate, so make sure whoever prescribes for you knows that you take it.

I'm unwell. Should I stop my steroid tablets too?

No. Steroid tablets must never be stopped suddenly, because your body needs time to resume making its own cortisol, and being ill does not change that. Illness can even mean the dose needs adjusting rather than stopping, which is a decision for your team or the doctors treating you. Keep taking them, carry your steroid card if you have one, and ask for advice promptly. Our guide to steroids in rheumatology explains the background.

Do I need to avoid crowds, grandchildren with colds, or eating out?

No. The aim is sensible habits, not a restricted life. Wash your hands well, take normal care with food hygiene, clean and cover cuts promptly, and use judgement around people who are obviously infectious, but you do not need to isolate yourself. Most people on these medicines catch ordinary coughs and colds and recover normally. The one contact to treat differently is chickenpox or shingles: if you have never had chickenpox and are exposed to either, contact your team promptly for advice.

Which vaccines should I have, and are any off limits?

Keep your yearly flu vaccine, stay up to date with COVID vaccination as advised, and have the pneumococcal vaccine when it is offered; these are non-live vaccines and are recommended for people on immune-suppressing medicines. The shingles vaccine is recommended too, for those who are eligible: the version now used in the UK is non-live, so it is suitable during treatment, unlike the older live one. Live vaccines, including some travel vaccines such as yellow fever, need specialist advice before you have them. Mention any planned travel or vaccinations at your reviews so the timing can be planned around your treatment.

My knee is hot and swollen and I have a fever. Can it wait for my clinic appointment next week?

No. A hot, swollen joint with a fever needs emergency assessment the same day, never a routine appointment. It can mean the joint itself is infected (septic arthritis), which can damage the joint quickly and make you seriously unwell, and it cannot be told apart from a flare or gout without examination and usually testing fluid from the joint. Go to A&E or call NHS 111 now, and tell them which medicines you take.