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URL of this page: //medlineplus.gov/ency/imagepages/9253.htm
Cytochrome b5 reductase blood test
Overview
Cytochrome b5 reductase is a blood enzyme that serves to maintain adequate iron levels in the red blood cells to maximize their oxygen-carrying capacity.
Review Date 1/10/2026
Updated by: Frank D. Brodkey, MD, FCCM, Associate Professor, Section of Pulmonary and Critical Care Medicine, University of Wisconsin School of Medicine and Public Health, Madison, WI. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
