Category: vitamin
Aliases: 25-hydroxycholecalciferol, 25(OH)D3, Calcidiol, Hidroferol, Rayaldee
The 25-hydroxy metabolite of cholecalciferol — bypasses the hepatic CYP2R1 hydroxylation step, so it raises serum 25(OH)D faster and more predictably than D3 (Tmax ~4 h vs ~12 h; ~3× steeper 25(OH)D response slope). Water-soluble after hydroxylation, so does not partition into adipose — useful in obesity and malabsorption where D3 has attenuated response. Still requires renal CYP27B1 to reach 1,25(OH)₂D.
PO: 360h