Role of Methotrexate in Psoriasis

Abstract

Psoriasis is a chronic immune-mediated inflammatory disease requiring effective systemic therapy in moderate to severe cases. Methotrexate (MTX), a folic acid antagonist, remains a cornerstone treatment due to its immunosuppressive, anti-inflammatory, and anti-proliferative effects. Despite the emergence of biologic agents, MTX continues to be widely used because of its cost-effectiveness and established clinical efficacy. This mini-review highlights the mechanism of action, pharmacokinetics, clinical indications, efficacy, safety profile, and monitoring of methotrexate in psoriasis. MTX acts by inhibiting dihydrofolate reductase and increasing adenosine levels, leading to suppression of keratinocyte proliferation and inflammatory cytokines such as TNF-α and interleukins. It demonstrates moderate efficacy, with a significant proportion of patients achieving clinical improvement. However, its use is limited by potential adverse effects, including hepatotoxicity, myelosuppression, and nephrotoxicity, necessitating careful patient selection and regular monitoring. MTX remains a reliable and cost-effective option for long-term management of psoriasis when used appropriately with adequate safety monitoring.