Combination therapies present another option in these difficult cases.2 Combination therapies for moderate-to-severe psoriasis may consist of two systemic agents or one systemic agent with topical or phototherapy. While there are numerous studies establishing the safety and efficacy of the latter, data regarding systemic combination therapy are limited. There is evidence that methotrexate (MTX) and cyclosporine (CsA) can be used together effectively.3 However, both of these medications are associated with significant side effects and consistent monitoring is required throughout treatment. Newer therapies such as systemic retinoids, phosphodiesterase inhibitors, and biologic drugs have comparatively more favorable side effect profiles.4 As such, physicians have begun to use these drugs in combination with traditional systemic agents and, in some cases, with one another.
There is a paucity of literature related to combination therapies involving these newer agents.5 Initial investigations suggest that biologic drugs in combination with CsA, MTX, acitretin, or