A Practical Approach to the Use of Methotrexate

Abstract

Background Methotrexate is approved by the Food and Drug Ad ministration for the treatment of severe, recalcitrant, and disabling psoriasis that is not adequately responsive to other forms of therapy. It is a systemic immunosuppressant that requires appropriate patient selection, screening laboratory values, and close monitoring before initiation of a maintenance regimen. Purpose This clinical review outlines a practical approach for the use of methotrexate in psoriasis. Methods A review of English-language literature between 1950 and 2010 was conducted, and the results are presented here. Results With close monitoring and appropriate patient selection, methotrexate is often an effective treatment option for moderate to severe psoriasis. Attention to individual patient risk factors and understanding of dosing regimens, contraindications, and “black box” warnings regarding methotrexate use can assist dermatologists in safely prescribing methotrexate for psoriasis treatment. Limitations This practical approach is based on an extensive literature review and the National Psoriasis Foundation and American Academy of Dermatology guidelines formulated after years of clinical practice, newer efficacy trials, and expert consensus regarding management in psoriasis patients. We have additionally incorporated some recommendations from our clinical experience at the University of California-San Francisco Psoriasis Treatment Center as indicated in the text. As always, clinical judgment and risk assessment should be used in selecting appropriate psoriasis patients for methotrexate therapy. Conclusion Methotrexate remains an effective, less expensive, and safe option for psoriasis patients who were previously unresponsive to other forms of therapy.

Low-dose methotrexate use in skin diseases: An old drug with new purposes

“…The primary mechanism of action for LD-MTX is not completely understood versus the well-known mechanism of action as an antimetabolite of HD-MTX in oncology treatments [2][3][4] . There are several approaches to the mechanism of action of LD-MTX (Fig.…”

“…One of the main mechanisms of the action of LD-MTX includes the inhibition of dihydrofolate reductase, an essential enzyme for folate metabolism, leading to the depletion of intracellular folate with thymidine synthesis inhibition 3 ; MTX is also an antagonist to folate metabolism, as well as it decreases the folate cofactors synthesis necessary for nucleic acid production 4 .…”

“…Before starting MTX, the following tests are required, including complete blood count, creatinine, liver function tests, and a pregnancy test in women with childbearing potential. In certain cases, B and C hepatitis, HIV testing, as well as the identification of latent tuberculosis might be considered 4 . Follow-up includes a complete blood count every 2-4 weeks in the 1 st month and every 2-3 months 4,6 .…”

“…In cases with a cumulative MTX dose of 3.5-4 g, liver biopsy or MTX withdrawal should be considered, although, in recent years, the use of the amino-terminal peptide of procollagen III levels may help to avoid or delay biopsy 4,6 .…”

Toxic epidermal necrolysis like reaction due to low-dose methotrexate in a case of cutaneous lupus erythematosus: A rare occurrence

“…MTX can be administered orally, intravenously, intramuscularly, or subcutaneously. This agent is approved for use by patients with malignancies, including cutaneous lymphomas, along with approval for psoriasis vulgaris,[ 8 9 ] psoriatic arthritis, and rheumatoid arthritis. However, it is widely used in dermatology practice (off label) for many other conditions, including bullous disorders, autoimmune connective tissue diseases (collagen vascular disorders), pityriasis rubra pilaris, pityriasis lichenoides et varioliformis acuta, sarcoidosis, and several unrelated diseases.…”