DMARDs: disease-modifying anti-rheumatic drugs

Most treatments for painful joints work on the symptom. Painkillers dull pain; anti-inflammatory tablets reduce swelling and stiffness; steroids calm inflammation quickly. All are useful, but they act on the effects of the disease, and when they wear off the underlying process carries on. Disease-modifying anti-rheumatic drugs, almost always shortened to DMARDs, are different. They act on the overactive immune process that drives inflammatory conditions such as rheumatoid arthritis, damping it down so that it does less harm. In doing so they can slow, and often halt, the joint damage that uncontrolled inflammation would otherwise cause. That is what disease-modifying means: changing the course of the illness itself, not just quietening its symptoms for a while.

This distinction shapes how the medicines are used. A painkiller can be taken when you need it and stopped when you do not. A DMARD is taken steadily, over the long term, to keep the disease quiet, and its benefit builds up over time rather than arriving with the first dose. In that sense it is closer to controlling blood pressure than to taking something for a headache.

One of the hardest things to accept about DMARDs is that they do not work straight away. It usually takes several weeks, and sometimes up to three months, before you notice a clear difference, and the full effect may not be reached until around six months of treatment. That is not a sign the medicine is failing; it is simply how these drugs work, gradually rebalancing an overactive immune system rather than switching it off.

The wait can be frustrating when you are in pain, which is why treatment is rarely left to the DMARD alone at the start. A short course of a steroid, or a steroid injection, is often used as a bridge to give relief while the slower medicine takes effect; our guide to steroids in rheumatology explains this role. The wait is worth it because what a DMARD offers is not a few hours of relief but a lasting change in how active the disease is, and the protection of the joints that comes with keeping inflammation controlled month after month.

DMARDs are not a single drug but a family of medicines that share a purpose while working in different ways. They fall into three broad groups.

Conventional DMARDs, sometimes called conventional synthetic DMARDs, are the long-established tablets, and usually the first choice. Methotrexate is the one most often used, with sulfasalazine, hydroxychloroquine and leflunomide among the alternatives, and they are sometimes combined. They work broadly, calming the overactive immune response as a whole. Methotrexate is taken once a week, not daily, and this is one of the most important safety points about it, because taking it more often than intended can cause serious harm.

Biologic DMARDs are newer, laboratory-made proteins that block one specific messenger or cell in the immune system rather than damping the whole response. Because they are proteins they cannot be taken as tablets, and are given by injection, usually under the skin, and in some hospital settings by a drip into a vein. They are typically used when conventional DMARDs have not controlled the disease well enough. Our guide to biologics and JAK inhibitors covers them in more detail.

Targeted synthetic DMARDs, better known as JAK inhibitors, are the most recent group. They are tablets that block enzymes called Janus kinases, which carry inflammatory signals inside cells. Like biologics, they target the process more precisely than the conventional drugs, and they are usually considered when earlier treatments have not done enough.

Modern DMARD treatment follows a principle called treat-to-target. Rather than starting a medicine and hoping for the best, the team agrees a clear goal with you, usually low disease activity or, better still, remission, meaning little or no active inflammation. Your response is then checked at regular reviews, and if the target has not been reached the treatment is stepped up or changed until it is.

This is why appointments and monitoring matter as much as the medicine itself. Judging whether inflammation is truly controlled takes more than asking how you feel, because a joint can still be quietly inflamed even when the pain has eased. Examination, blood tests and, where helpful, point-of-care ultrasound during the consultation can show whether inflammation is genuinely settled, which guides the next step. The aim throughout is to use the least treatment that keeps the disease quiet.

Because DMARDs act on the immune system, they share a set of safety themes whichever one you are taking.

Regular blood tests are part of treatment, not an optional extra. DMARDs can occasionally affect the liver, the blood count or the kidneys, usually without any warning symptoms, and monitoring is how these changes are picked up early and dealt with before they cause harm. Our guide to rheumatology blood tests explains what is checked and why. Keeping up with monitoring is one of the most important things you can do to stay safe on treatment.

Infection awareness matters because calming an overactive immune system also slightly reduces its ability to fight infection. Most people on DMARDs do not get frequent infections, but an infection can be harder to shake off, and its usual warning signs can be blunted. It is worth telling any healthcare professional that you take a DMARD, and seeking advice early if you develop a fever or feel unwell. Our guide to infections and arthritis medicines goes into this further.

Vaccinations need a little planning: live vaccines are usually avoided while on these medicines, whereas non-live vaccines are recommended and encouraged. These include the annual flu vaccine, the pneumococcal vaccine and the shingles vaccine: the version now used in the UK is a non-live one, so it is suitable during immune-suppressing treatment, unlike the older live vaccine, and is offered to those who are eligible. Our guide to vaccinations explains who qualifies and how the timing is planned.

Planning a pregnancy needs a conversation in advance. Some DMARDs, such as methotrexate and leflunomide, must be stopped well before trying to conceive, while others, such as hydroxychloroquine and sulfasalazine, are often considered safe to continue, and the timing differs for each medicine. None of this should be worked out alone or at the last minute; our guide to arthritis, autoimmune conditions and pregnancy explains why raising it early gives you the most choice.

Never stop a DMARD without advice. It can be tempting to stop when you feel well, or when you feel the medicine is not helping, but stopping suddenly can let the disease flare, and for some medicines that flare is hard to bring back under control. If side effects are troubling you, the answer is to discuss them rather than to stop unannounced, so that the dose can be adjusted or the medicine changed safely.

While on a DMARD, some symptoms deserve prompt attention rather than waiting for a routine appointment. Contact your rheumatology team or GP promptly if you:

• Develop a fever, a persistent sore throat, or feel generally unwell, which can be the first sign of an infection that needs attention
• Notice unusual bruising or bleeding, or become unusually breathless or tired, which can point to an effect on the blood count
• Develop a new widespread rash, mouth ulcers, or yellowing of the skin or eyes
• Come into contact with chickenpox or shingles and have not had chickenpox yourself, as this can occasionally need preventive treatment

A single hot, swollen, very painful joint, especially with a fever, needs same-day assessment, because a joint infection has to be ruled out quickly and is never something to leave for a routine visit.

Seek emergency care (999 or A&E) for the signs of serious infection, such as a high fever with shivering, confusion, a rash that does not fade when pressed, severe breathlessness or feeling very unwell, as infections can occasionally become serious quickly when the immune system is damped.

DMARDs ask something of you that painkillers do not: patience while they take effect, the commitment of regular blood tests, and a willingness to stay on treatment even when you feel well. In return they offer something painkillers cannot, which is a real change in the course of the disease and lasting protection for the joints. The monitoring and the reviews are not red tape; they are what makes it possible to use these medicines both effectively and safely, catching problems early and keeping the disease quiet over years rather than weeks. Used this way, with a clear target and careful follow-up, DMARDs have transformed what it means to live with inflammatory arthritis. A specialist assessment is where the right medicine, the right monitoring and a plan that fits your life are decided together.

What does 'disease-modifying' actually mean?

It means the medicine works on the disease process itself, not just its symptoms. A painkiller or anti-inflammatory tablet eases pain and stiffness while you take it, but the underlying inflammation carries on once it wears off. A DMARD damps down the overactive immune response that is driving the condition, which can slow or halt the joint damage that inflammation would otherwise cause. That is why it is taken steadily over the long term rather than only when symptoms flare.

How long before a DMARD starts working?

Longer than most people expect. It usually takes several weeks, sometimes up to three months, before you notice a clear difference, and the full benefit may not arrive until around six months. This is normal and not a sign of failure. Because the wait can be hard when you are in pain, a short course of a steroid is often used as a bridge to settle things while the DMARD gets going; our guide to steroids in rheumatology explains that role.

Do I really need to keep taking it when I feel well?

Almost always, yes, and feeling well is usually a sign the medicine is doing its job rather than a reason to stop. Never stop a DMARD without advice. Stopping suddenly can let the disease flare, and for some medicines that flare is hard to bring back under control. If the medicine is causing side effects, or you simply want to review it, raise it with your rheumatology team so any change is made safely.

Why do I need regular blood tests?

DMARDs can occasionally affect the liver, the blood count or the kidneys, usually without any warning symptoms, so regular blood tests are how those changes are picked up early and dealt with before they cause harm. The monitoring is a routine, expected part of treatment, not a sign that something is wrong. Our guide to rheumatology blood tests sets out what is checked and why.

Should I be worried about infections?

Most people on DMARDs do not get frequent infections, but because these medicines calm the immune system, an infection can be a little harder to shake off and its usual warning signs can be blunted. The sensible approach is to be alert rather than anxious: tell any healthcare professional that you take a DMARD, keep up with recommended vaccinations such as the annual flu jab, and seek advice the same day if you develop a fever or feel unwell. Our guide to infections and arthritis medicines explains this further.