has role has parent hydride primary alpha-hydroxy ketone tertiary alpha-hydroxy ketone 16alpha-hydroxy steroid glucocorticoid 17alpha-hydroxy steroid 21-hydroxy steroid 11beta-hydroxy steroid anti-inflammatory drug 20-oxo steroid 3-oxo-Delta(4) steroid fluorinated steroid anti-allergic agent C21-steroid hormone pregnane triamcinolone A C<small>₂₁</small>-steroid hormone that is 1,4-pregnadiene-3,20-dione carrying four hydroxy substituents at positions 11β, 16α, 17α and 21 as well as a fluoro substituent at position 9. Used in the form of its 16,17-acetonide to treat various skin infections.