This information is for people who have rheumatoid arthritis. It tells you about taking infliximab along with methotrexate, which are both treatments for rheumatoid arthritis. It is based on the best and most up-to-date research.
Does it work?
Yes. If other drugs have not worked, there's good evidence to show that taking infliximab and methotrexate together can help.
You'll usually only be offered these drugs if other treatments haven't helped, or have stopped working.
What is it?
Infliximab is a type of medicine called an anti-TNF drug. Like some of the other treatments for rheumatoid arthritis, anti-TNF drugs don't just help with pain. They also slow down the damage to your joints. Drugs that do this are called disease-modifying anti-rheumatic drugs (DMARDs for short). Anti-TNF drugs are a newer type of DMARD. You may also hear them called biologic drugs, or biologics.
Several anti-TNF drugs are available in the UK. This information is about infliximab. To find out about the others, see etanercept, adalimumab, certolizumab, and golimumab.
The brand name for infliximab is Remicade. It is given as a drip into your vein (also called an IV or intravenous infusion). You'll have your first infusion followed by more at two and six weeks. After that you'll have an infusion every eight weeks.
You'll be given infliximab along with a drug called methotrexate.  Methotrexate is also a DMARD, and you'll take it as a tablet once a week. To learn more, see Methotrexate.
Guidelines for doctors say you should only be prescribed infliximab if you have not been helped by two other DMARDs. One of the DMARDs that you should have tried is methotrexate. You may also be offered infliximab if you can't take other drugs because of side effects.  You should also have a check-up every six months to make sure the drug is working.
How can it help?
Taking infliximab and methotrexate together can reduce the pain and swelling in your joints. This may make it easier for you to do things like going shopping, doing the housework, having sex, seeing your friends and doing other things you enjoy.
In studies, more than half the people taking this combination of drugs had some improvement in their symptoms after six months, compared with only 2 in 10 who took just methotrexate. 
Taking infliximab plus methotrexate may also help to stop your joints wearing down. 
How does it work?
TNF (or tumour necrosis factor) is a chemical in your blood. Anti-TNF drugs stop this chemical working. Scientists think that this chemical makes your immune system attack the lining of your joints. This causes swelling and pain.
Doctors are not sure how methotrexate works. But it seems to also affect your immune system, stopping it from attacking the lining of your joints.