Methotrexate Induced Toxicity: A Clinical Case Report And Review Of Literature

Chronic plaque psoriasis is a persistent inflammatory skin disorder often treated with methotrexate, an antifolate medication known for its immunosuppressive and anti-inflammatory properties. However, methotrexate poses significant toxicity risks, particularly impacting the hematopoietic, hepatic, renal, and gastrointestinal systems. This report presents a case of a 29-year-old male with psoriasis who developed acute methotrexate toxicity after being prescribed a cumulative dose of 155 mg for a flare-up. The patient exhibited generalized skin ulcerations, oral erosions, gastrointestinal distress, and systemic symptoms including high-grade fever. Laboratory tests confirmed myelosuppression and hepatotoxicity, although renal function remained unaffected. Immediate discontinuation of methotrexate, combined with folinic acid rescue therapy, intravenous hydration, urine alkalization, and supportive care, led to gradual clinical improvement. The management of methotrexate toxicity centres around early intervention with folinic acid, which replenishes folate stores and restores DNA synthesis, as well as hydration and urine alkalization to enhance drug elimination. In cases of severe toxicity, glucarpidase offers a rapid reduction in methotrexate levels, particularly in patients with renal impairment. Emerging therapies, such as nanomedicine and pharmacogenomic testing, offer potential for more targeted treatments and reduced toxicity risk. This case highlights the importance of vigilant monitoring and proactive management of methotrexate toxicity to prevent irreversible organ damage and improve patient outcomes