ExplanationDefinition
Methotrexate is a long-term disease-modifying antirheumatic drug (DMARD), a basic therapeutic agent in the treatment of rheumatoid arthritis and psoriatic arthritis. It is used in cases of high disease activity. In case of ineffectiveness or decreasing effectiveness, methotrexate can be combined with other DMARDs.
In therapy with methotrexate, undesirable side effects can be counteracted with folic acid preparations without loss of efficacy. Furthermore, Methotrexate is used in the treatment of various malignant tumor diseases. This indication will not be discussed in detail here.
Trade names
Lantarel ® from Wyeth Pharma GmbHMetex ® from medacMTXu. v. a.
Common typing errors
Metotrexate, metotrexate, methotrexate, methotrexad structural formula
Active ingredient
Methotrexate disodium applications of methotrexate are severe form high disease activity of rheumatoid arthritis and psoriatic arthritis. Furthermore, methotrexate (e.g. Lantarel ®Metex ®) is used for the most severe forms of psoriasis vulgaris, which cannot be treated sufficiently with other forms of therapy. Methotrexate is also used in early forms of ectopic pregnancy.
Dosage forms
- TabletsFilm coated tablets
- Solution
- Infusion
Effect
Methotrexate is an antagonist of folic acid (folic acid antagonist) and as an antimetabolite inhibits the proliferation of rapidly dividing cells. As an immunosuppressive agent, methotrexate also weakens undesirable body defensive reactions and has an anti-inflammatory effect. An improvement of the symptoms can usually be expected after 4-8 weeks. After discontinuing methotrexate, the symptoms may reoccur (see: discontinuing cortisone). Treatment with methotrexate is generally longer-term.
Application
The tablets should be taken unchewed with plenty of liquid (no dairy products), preferably in the evening (once a week), preferably not with meals. Contact with skin or mucous membranes should be avoided – otherwise rinse the affected areas immediately with plenty of water.
Dosage
For rheumatoid arthritis and psoriatic arthritis the initial dose is 7.5 mg once a week, always on the same day of the week. In case of insufficient effect and good tolerability the dose may be gradually increased by 2.5 mg. A weekly dose of 20 mg methotrexate should not be exceeded. For psoriasis vulgaris the initial dose is 7.5 – 22.5 mg methotrexate once a week, always on the same day of the week.
If the effect is insufficient and the patient is well tolerated, the dose can be gradually increased. A weekly dose of 30 mg methotrexate should not be exceeded. After the desired treatment success has been achieved, the dose should, if possible, be gradually reduced to the lowest still effective maintenance dose. Methotrexate (e.g. Lantarel ®Metex ®MTX ®) should be used at reduced doses and under close medical supervision for
- High age
- Poor general condition
- Fluid accumulation in the abdominal cavity or between the lung sheets (ascites, pleural effusion)
- Strong overweight
- Former, high-dose vitamin A therapy for psoriasis
- Restriction of lung function
