The therapy of psoriasis has changed radically in the last 20 years. It has evolved from aiming at the functions of different cells involved in its pathogenesis (keratinocytes and cells of the immune system) to targeting highly specific immune mediators. Biologic therapy itself has evolved further, with new antibodies directed to interleukin (IL)-17 and IL-23 achieving higher disease clearance when compared with those directed towards other mediators such as tumour necrosis factor (TNF). Remarkably, the most recently introduced armamentaria include molecules with much better safety profiles, causing less overall immunosuppression and lower risk of tuberculosis reactivation, something relevant for South American countries with a high prevalence of tuberculosis...