Epiestriol

Epiestriol () (brand names Actriol, Arcagynil, Klimadoral), or epioestriol (), also known as 16β-epiestriol or simply 16-epiestriol, as well as 16β-hydroxy-17β-estradiol, is a minor and weak endogenous estrogen, and the 16β-epimer of estriol (which is 16α-hydroxy-17β-estradiol). Epiestriol is (or has previously been) used clinically in the treatment of acne. In addition to its estrogenic actions, epiestriol has been found to possess significant anti-inflammatory properties without glycogenic activity or immunosuppressive effects, an interesting finding that is in contrast to conventional anti-inflammatory steroids such as hydrocortisone (a glucocorticoid).

{| class="wikitable center sortable mw-collapsible mw-collapsed" style="width:600px; text-align:left; margin-left:auto; margin-right:auto; border:none;" |+ class="nowrap" | Relative affinities (%) of epiestriol and related steroids |- ! Compound || || || || || || || |- | Estradiol || 2.6 || 7.9 || 100 || 0.6 || 0.13 || 8.7 || <0.1 |- | Alfatradiol || <1 || <1 || 15 || <1 || <1 || ? || ? |- | Estriol || <1 || <1 || 15 || <1 || <1 || ? || ? |- | 16β-Epiestriol || <1 || <1 || 20 || <1 || <1 || ? || ? |- | 17α-Epiestriol || <1 || <1 || 31 || <1 || <1 || ? || ? |- class="sortbottom" | colspan="10" style="width: 1px;" | Values are percentages (%). Reference ligands (100%) were progesterone for the , testosterone for the , estradiol (medication)| for the , for the , aldosterone for the , for , and cortisol for . |}