Methotrexate
Methotrexate is a systemic medication that has been used to treat psoriasis for over forty years. It is an effective and widely used treatment for both psoriasis and the joint disease that is sometimes associated with psoriasis called psoriatic arthritis. Click here to find out more information about psoriatic arthritis.
How does it work?
Methotrexate prevents cells from dividing so quickly. It can reduce the rapid production of skin cells that happens with psoriasis. It also suppresses the activity of certain cells of the immune system (T-cells).
When is it used?
Methotrexate may be used if your psoriasis is severe and if other therapies have not been effective. Your healthcare team will look at your medical history carefully to decide whether you can have methotrexate.
How is it taken?
Methotrexate is normally taken as a pill once a week. It may also be given as injections. Your healthcare team may decide that these weekly doses should be split into separate doses. There is no specific limit on the amount of time that methotrexate can be taken for, although your healthcare professional will regularly monitor you for side effects, particularly if you are taking methotrexate for a long period of time.
If your psoriasis improves, your healthcare team will normally reduce the dose to the lowest effective dose, to reduce the risks of any side effects. It may also be possible to restart therapy with topical treatments following improvements with methotrexate. If your psoriasis does not improve your healthcare team may increase the dose or combine it with another systemic medication, or perhaps opt for a different treatment altogether.
Advantages and disadvantages
Methotrexate is often effective in people whose psoriasis has not improved with topical treatments.
Methotrexate can cause a range of side effects. The most common of these are nausea and vomiting, fatigue (tiredness), headaches, hair loss, loss of appetite, eye irritation, and a reduction in the levels of white blood cells.
Because methotrexate is also associated with a risk of liver damage, your healthcare team will probably carry out regular check-ups during treatment. These check ups will normally include blood samples being taken, so that your healthcare team can monitor any early signs of liver damage.
You should not take methotrexate if you are pregnant. For both men and women taking methotrexate, you must speak to your healthcare team if you are trying for a baby, as it is likely that you will have to stop your methotrexate for a period of time before trying to conceive.
If you have any questions about methotrexate, you may want to discuss them with a member of your healthcare team.