Precursor to metabolite: Ergocalciferol to Calcifediol

Ergocalciferol is converted to Calcifediol by CYP2R1.

Ergocalciferol mascot — mnemonic cartoon — Visual mnemonic: Ergocalciferol mascot

The pair

Ergocalciferol — Prescription vitamin D2; cleared faster than D3, so D3 is usually preferred.
Calcifediol — 25-hydroxyvitamin D and calcitriol precursor for secondary hyperparathyroidism.

Ergocalciferol · Calcifediol · Open Ergocalciferol in the interactive console ↗