Methotrexate

About methotrexate

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 breastfeeding.

• If you are unwell with an infection.

• If you have a stomach ulcer.

• If you regularly suffer from mouth ulcers or cold sores (herpes).

• 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 have an addiction to alcohol

• If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well 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 oral medicine to take (tablets or liquid medicine), or arrangements will be made for you to attend a clinic to receive methotrexate as an injection.

• Pre-filled injection pens are also available for you to administer by yourself at home, once you have been shown the correct technique by your doctor or nurse.

• Methotrexate is prescribed as one dose each week, to be taken on the same day each week. You must not take methotrexate every day.

• If you have been prescribed tablets, 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.

• 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 are taking the oral liquid medicine, or you are giving it to a child, make sure you measure the correct dose carefully using the oral syringe provided. It is a good idea to have a drink of water after taking your dose.

• 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 folic acid tablets while you are on methotrexate. This is to help protect healthy cells in your body and reduce unwanted side-effects. Your doctor will tell you 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 at least six 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).

• This medicine lowers your natural protection against infection. It is important to protect yourself from serious illness by having any vaccinations your doctor offers you. If you live with other people they can also help protect you by having their own vaccinations.

• Some vaccines may not be suitable for people with lowered immune systems. Always let the person vaccinating know that you are taking this medicine.

• Methotrexate may cause your skin to become more sensitive to sunlight than normal. Use a sunscreen that protects against UVA light and has a sun protection factor (SPF) of at least 15, especially in strong sunlight or until you know how your skin reacts. Do not use sunbeds.

• 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.

• If you are having an operation or dental treatment tell the person carrying out the treatment that you are taking methotrexate. Nitrous oxide, an anaesthetic that you inhale, can interfere with the effects of methotrexate.

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:

Important: if you develop a combination of the following rarer or more severe side-effects, 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.

• Bottles of oral liquid medicine should be disposed of three months after first opening. It is a good idea to write on the label the date you opened the bottle.

Important information about all medicines