“…Small molecule PDE4 inhibitors like apremilast, which increase the concentration of intracellular cyclic AMP, are an example for drugs that can be effective in the management of scalp psoriasis, [101][102][103] but are also HFprotective in that they can inhibit the development of experimentally Note: Even though the pilosebaceous unit is clearly affected by scalp psoriasis on multiple levels and the percentage of catagen/telogen HFs can be increased, as summarized in the table, even with severe scalp involvement, psoriatic alopecia occurs only in a small minority of patients. 28,184,185 Moreover, only in a minority of patients there is loss of visible hairs within psoriatic plaques. 29…”