Systemic therapies for psoriasis: methotrexate, retinoids, and cyclosporine.

Despite the current use and ongoing development of the biological therapies 'traditional' systemic agents will continue to form a key part of the therapeutic armamentarium for patients with severe psoriasis. Long-term maintenance therapy with retinoids and methotrexate is cost-effective and, for many patients with psoriasis, life changing. Regular monitoring is required for both treatments, particularly methotrexate to prevent significant bone marrow suppression and hepatotoxicity. Ideally, cyclosporine should be used for short courses of 3 to 4 months duration, within which it provides excellent disease control. Close assessment of renal function and blood pressure is essential.