acitretin

noun

ac·​i·​tret·​in ˌa-sə-ˈtre-tᵊn 

: a retinoid drug C₂₁H₂₆O₃ that is the principal metabolite of etretinate and is taken orally in the treatment of severe psoriasis

Acitretin, although less effective as monotherapy, approaches methotrexate and cyclosporine in efficacy when combined with PUVA or UVB phototherapy.

—Lynne Lamberg, The Journal of the American Medical Association

Note: Acitretin is marketed under the trademark Soriatane.