Methotrexate is used to treat a number of different conditions.
Take one dose each week, on the same day of the week.
Two strengths of tablet are available - 2.5 mg and 10 mg. Each time you collect a supply it is important that you check to make sure you get the same strength as you have had before.
Do not take any painkilling medicines containing aspirin or ibuprofen with methotrexate (unless prescribed by your doctor).
|Type of medicine||An antimetabolite anti-cancer medicine|
|Used for||Cancers; rheumatoid arthritis; psoriasis|
|Also called||Maxtrex®; Metoject®|
|Available as||Tablets and injection|
Methotrexate is used to treat conditions where some kind of 'over-activity' in the body is causing problems.
In cancers, certain cells in the body grow and multiply too fast. These cells then spread and damage nearby tissues. Methotrexate works by stopping the growth of the cancer cells. It does this by affecting the genetic material of the cells and this reduces the number of new cells that your body makes.
It is thought that rheumatoid arthritis is caused by over-activity of the immune system. Your immune system normally protects your body from attack by things that would harm it, such as germs. However, in rheumatoid arthritis, your immune system starts attacking parts of your own body as if they were foreign. Although it isn't known exactly how methotrexate works in rheumatoid arthritis, it is thought to have an effect on the way your immune system works.
In psoriasis, the skin cells in the outer layer of your skin multiply faster than normal. This causes thickened areas of skin. Methotrexate helps in psoriasis by reducing the overproduction of skin cells.
Methotrexate is also prescribed for some conditions which are not mentioned in this leaflet. If you have been prescribed it for any other condition, ask your doctor if you need more information about your treatment.
Before taking methotrexate
Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking methotrexate it is important that your doctor knows:
- If you are pregnant or intend to have children in the future.
- If you are breast-feeding.
- If you are unwell with an infection.
- If you have a stomach ulcer.
- If you have any gastrointestinal problems, or diarrhoea.
- If you have any problems with the way your liver works or how your kidneys work.
- If you have a blood disorder.
- If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
- If you have ever had an allergic reaction to a medicine.
How to take methotrexate
- Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack and any other written information you are given. The manufacturer's leaflet will give you more information about methotrexate and a full list of the side-effects which you may experience from having it.
- Methotrexate will be prescribed for you by a specialist doctor who is experienced in treating your condition.You will either be supplied with tablets to take, or, arrangements will be made for you to attend a clinic to receive methotrexate as an injection.
- If you are given tablets, you will be prescribed one dose each week. You must not take methotrexate every day. Your doctor will tell you how many tablets to take each week - this will be calculated according to your condition, or to your weight and height. It is important that you take the correct number of tablets on the same day of the week. Take the tablets exactly as your doctor tells you to. The dose you are prescribed will be printed on the label of your pack to remind you what your doctor has said.
- Methotrexate tablets are available in two strengths: 2.5 mg and 10 mg. You will only be given one strength of tablet. If your tablets look different to your last supply speak with your doctor or pharmacist for advice.
- Swallow the tablets with a drink of water. You can take methotrexate before or after food.
- If you forget to take a dose, take it as soon as you remember, if it is within two days of when you should have taken it. If you have missed your dose by more than two days, contact your doctor or clinic for advice about what to do. Never take two doses together to make up for a missed dose.
- You may be asked to take folinic acid tablets while you are on methotrexate. This is to help reduce unwanted side-effects. Your doctor will tell which day (or days) of the week to take it.
Getting the most from your treatment
- It is important for you to know why methotrexate has been prescribed for you as well as how you take it. If you are unsure why you are taking it, or what dose to take, or which day of the week to take it on, ask your doctor.
- You must try to keep your regular appointments with the doctor or hospital. This is so your progress can be checked. You will need to have regular blood tests during your treatment with methotrexate.
- Do not take any painkilling medicines containing aspirin or non-steroidal anti-inflammatory drugs (such as ibuprofen and diclofenac) unless they have been prescribed for you by your doctor. Also, do not take any vitamin preparations which contain folic acid unless prescribed by your doctor. This is important because the medicines listed here can interfere with methotrexate and cause you harm. Some medicines that can be bought over the counter can contain these medicines, so check with your pharmacist if you are unsure.
- If you drink alcohol, ask your doctor for advice. Your doctor may recommend that you do not drink any alcohol while you are on this medicine.
- You must avoid getting pregnant or fathering a child while you are on methotrexate. You must also avoid this for a further three months after your treatment has finished. Make sure you have discussed with your doctor which types of contraception are suitable for you and your partner. You may also want to ask your doctor for family planning advice if you intend to have children in the future (particularly if you are a man).
- Try to handle the tablets as little as possible, and wash your hands after touching them.
- Any unwanted tablets or any waste from injections must be disposed of in a special way. If you need to dispose of methotrexate, ask your local pharmacy for advice.
- Do not have any immunisations (vaccinations) while you are taking this medicine and for several months afterwards, without talking to your doctor first. Methotrexate lowers your body's resistance and there is a chance that you may get an infection from some vaccines.
- If you are having an operation or dental treatment tell the person carrying out the treatment which medicines you are taking.
Can methotrexate cause problems ?
Methotrexate may lower the number of white cells in your blood, increasing the chance of you getting an infection. You should take certain precautions to reduce the risk of infection - where possible, avoid people who you know are unwell, and let your doctor know if you think you are getting a sore throat or if you have a high temperature.
Your doctor will discuss with you the possibility of unwanted side-effects of treatment. The table below contains some of the most common ones associated with methotrexate. You will find a full list in the manufacturer's information leaflet supplied with your tablets/injection. Let your doctor know if you experience any of the following:
|Common methotrexate side-effects||What can I do if I experience this?|
|Feeling feverish, sore throat, infections (due to changes in the number of blood cells)||Let your doctor know about this as soon as possible|
|Feeling or being sick, loss of appetite, abdominal discomfort, diarrhoea||Eat simple meals (avoid rich or spicy foods). If this becomes troublesome, let your doctor know|
|Sore mouth, mouth ulcers||Speak with your doctor about this|
Important: If you develop any of the following rarer but more serious symptoms, let your doctor know straightaway:
- Sore throat, mouth ulcers, any unusual bruising.
- Severe abdominal pain, being sick, dark urine.
- Feeling breathless, cough, high temperature.
- A severe skin rash.
If you experience any other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.
How to store methotrexate
- Keep all medicines out of the reach and sight of children.
- Store in a cool, dry place, away from direct heat and light.
Important information about all medicines
Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital. Take the container with you, even if it is empty.
This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.
Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.
If you have any questions about this medicine ask your pharmacist.
Further reading & references
- Manufacturer's PIL, Maxtrex® Tablets 2.5 mg; Pharmacia Limited, The electronic Medicines Compendium. Dated April 2012.
- Manufacturer's PIL, Maxtrex® Tablets 10 mg; Pharmacia Limited, The electronic Medicines Compendium. Dated April 2012.
- British National Formulary; 66th Edition (September 2013) British Medical Association and Royal Pharmaceutical Society of Great Britain, London
Disclaimer: This article is for information only and should not be used for the diagnosis or treatment of medical conditions. EMIS has used all reasonable care in compiling the information but make no warranty as to its accuracy. Consult a doctor or other health care professional for diagnosis and treatment of medical conditions. For details see our conditions.
Dr John Cox