Ferrous iron ion (Fe²⁺)

The ferrous iron ion is the oxidation state +2 form of elemental iron (Fe²⁺), also called iron(II) or ferrous ion[6][7]. It is a pale green, water-soluble ion, playing a key role in many biological processes as a cofactor in enzymes and as the core metal in heme involved in oxygen transport[7]. In biological systems, Fe²⁺ is essential for the function of hemoglobin, myoglobin, cytochromes, and numerous metalloenzymes. Imbalance of ferrous iron causes clinical problems including anemia (deficiency) or tissue damage (overload). Drugs related to Fe²⁺ are mostly iron supplements for deficiency or chelators used to treat overload. However, Fe²⁺ is not a receptor, enzyme, or transporter, and thus is not a therapeutic target in the sense used in drug discovery[5][6][7]. Note: “Ferrous iron ion” (Fe²⁺) is an essential trace element and simple ion, rather than a classical druggable molecular target. Most drugs interact with Fe²⁺ non-selectively via supplementation or chelation rather than via targeted receptor–ligand interactions.

Other names

Iron(II) ionFe(II)Iron(II)Ferrous ionIron, ion (Fe²⁺)IRONII

Chelation (binding and sequestration of Fe²⁺ to reduce bioavailability) Supplementation (providing bioavailable Fe²⁺ to treat deficiency)