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Ferrous Oxide

Excipient (pharmacologically inactive substance)

Medically reviewed by Last updated on June 15, 2020.

What is it?

Ferrous oxide (FeO), or iron (II) oxide, is an iron oxide and exists as a black powder. It is not rust (ferric oxide). Iron(II) oxide makes up part of the earth's mantle. Synthetic iron oxide is approved for used as a pigment in certain foods, cosmetics, contact lenses and drugs.[1][2]

Top Medications with this excipient


[1] [1] Ingredient Glossary - iron oxides. Accessed March 30, 2014.

[2] FDA. For Industry. Summary of Color Additives for Use in the United States in Foods, Drugs, Cosmetics, and Medical Devices. Accessed April 1, 2014.

Further information

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