Methotrexate
A DRUG Information Sheet
Why am I being prescribed methotrexate?
Methotrexate is used to treat several different types of rheumatic disease, including rheumatoid arthritis and psoriatic arthritis. Methotrexate can reduce inflammation and also can affect the immune system (the body's own defence system). One of its actions is to reduce the activity of the immune system, so it is always used with care.
When and how do I take methotrexate?
Methotrexate is usually taken in tablet form ONCE A WEEK on the same day. It should be taken with food. The tablets should be swallowed whole and not crushed or chewed.
Methotrexate may also be given once a week by injection – subcutaneous (an injection under the skin, like insulin injections for diabetes), or intramuscular (into the buttock or thigh). Methotrexate has also been licensed for intravenous use (injection into the vein).
What dose do I take?
Methotrexate tablets are usually 2.5 mg. A 10 mg tablet is also available, although less often dispensed, and to avoid confusion it is recommended that only the 2.5 mg tablet be used. The two strengths are different shapes but are a very similar colour, so you should always check the dose is correct.
Your doctor will advise you about what dose you should take. Usually you will start on a low dose (e.g. 5–10 mg a week). Your doctor may then increase this. Injected methotrexate is normally only used if the tablets are not well tolerated.
How long will methotrexate take to work?
Methotrexate does not work immediately. It may be 3–12 weeks before you notice any benefit.
What are the possible risks or side-effects?
In some patients methotrexate can cause a feeling of sickness, diarrhoea, mouth ulcers, hair loss and skin rashes.
Taking methotrexate can affect the blood count (one of the effects is that fewer blood cells are made) and can make you more likely to develop infections. If you develop a sore throat or other infection, a fever, unexplained bruising or bleeding, if you develop jaundice (eyes or skin turning yellow), or if you develop any new symptoms after starting methotrexate, you should tell your doctor or rheumatology nurse specialist straight away. If any of these symptoms are severe, you should stop methotrexate and see your doctor immediately.
Rarely, methotrexate causes inflammation of the lung with breathlessness. If you become breathless, you should stop methotrexate and see your doctor immediately.
If you have not had chickenpox but come into contact with someone who has chickenpox or shingles, or if you develop chickenpox or shingles, you should stop methotrexate and see your doctor immediately as you may need special treatment. This is because chickenpox and shingles can be severe in people on treatment such as methotrexate which has effects on the immune system. Therefore you may require antiviral treatment.
Most doctors prescribe folic acid tablets to patients who are taking methotrexate as this can reduce the likelihood of side-effects. It is often recommended that folic acid should be taken once a week only: some doctors advise that it should not be taken on the same day as methotrexate.
What other treatments could be used instead of methotrexate?
A number of other drugs are used in the treatment of rheumatoid arthritis and related conditions (see arc leaflet 'Drugs and Arthritis'). Your doctor will discuss these other options with you.
Do I need any special checks while on methotrexate?
Because methotrexate can affect the blood count and sometimes cause liver problems, your doctor will arrange for you to have a blood test before you start treatment and regular blood checks while on methotrexate. You may be asked to keep a record booklet with your blood test results. Bring this with you when you visit your GP or the hospital. Your doctor may also request a chest x-ray before you start treatment, and sometimes lung function (breathing) tests. You must not take methotrexate unless you are having regular checks.
May I take other medicines along with methotrexate?
Methotrexate may be prescribed along with other drugs in treating your condition. Some drugs interact with methotrexate, so you should discuss any new medications with your doctor before starting them, and you should always tell any other doctor treating you that you are taking methotrexate.
Special care is needed with non-steroidal anti-inflammatory drugs (NSAIDs). You may only take NSAIDs if they are prescribed to you by your doctor. You should also avoid the drugs trimethoprim and co-trimoxazole (Septrin), which may be prescribed for infections.
Methotrexate is not a painkiller. If you are already on painkillers you may carry on taking these as well as methotrexate, unless your doctor advises otherwise.
Do not take over-the-counter preparations or herbal remedies without discussing this first with your doctor, rheumatology nurse or pharmacist.
Can I have immunisations while on methotrexate?
It is recommended that you should not be immunised with 'live' vaccines such as yellow fever. However, in certain situations a live vaccine may be necessary (for example rubella immunisation in women of childbearing age), in which case your doctor will discuss the possible risks and benefits of the immunisation with you.
Pneumovax and yearly flu vaccines are safe and recommended.
May I drink alcohol while taking methotrexate?
If you drink alcohol you should only drink it in small amounts because methotrexate and alcohol can interact and damage your liver. Discuss this with your doctor.
Does methotrexate affect fertility or pregnancy?
Methotrexate can reduce fertility and is likely to harm an unborn baby. So it must not be taken during pregnancy. Both men and women using this drug should take contraceptive precautions. After stopping methotrexate you should continue taking contraceptive precautions for at least 3 months, and some doctors advise up to 6 months. If you are planning a family, or if you become pregnant while taking methotrexate, you should discuss this with your doctor as soon as possible.
What about breastfeeding?
You should not breastfeed if you are taking methotrexate.
Where can I obtain further information?
If you would like any further information about methotrexate, or if you have any concerns about your treatment, you should discuss this with your doctor, rheumatology nurse or pharmacist.
Remember to keep all medicines out of reach of children.
PLEASE NOTE: We have made every effort to ensure that the content of this information sheet is correct at time of going to press, but remember that information about drugs may change. This sheet does not list all the uses and side-effects associated with this drug. For full details please see the drug information leaflet which comes with your medicine. Your doctor will assess your medical circumstances and draw your attention to any information or side-effects which may be relevant in your particular case.
