What is Ferric Oxide Red USP–NF used for?
Ferric oxide red (also called red iron oxide; typically an insoluble pigment) is used mainly as a colorant in drug products and other materials where a stable red color is needed. In pharmacy and supplements, it commonly appears in formulations to tint tablets, capsules, and topical products, including to help with product identification and uniform appearance.
How is Ferric Oxide Red USP–NF used in drug products?
In medicines, ferric oxide red USP–NF is generally used as a non-active ingredient (an excipient), most often as:
- A coloring agent for oral solid dosage forms (for example, tablets and capsules).
- A coloring agent for some topical dosage forms, depending on the product’s labeling and formulation.
Because it is an iron oxide pigment, it is valued for being chemically stable and not easily affected by light or air compared with many other dyes.
What does “USP–NF” mean for Ferric Oxide Red?
“USP–NF” refers to standards set by the U.S. Pharmacopeia and the National Formulary. When a supplier states “Ferric Oxide Red USP–NF,” it typically means the material is manufactured and tested to meet those pharmacopeial specifications (such as identity, purity, and other quality criteria) for pharmaceutical or compendial use.
Is it safe—what are common patient concerns?
For patients, the key points are usually about:
- Inertness: it is a pigment/excipient, not a therapeutic drug.
- Impurities/quality: USP–NF grade is meant to reduce variability and ensure quality controls.
- Allergy concerns: true reactions are uncommon, but any excipient can be an issue for sensitive individuals. If a patient has a history of dye/pigment sensitivity, they may ask the pharmacist to check excipient listings for the exact product.
Where else is Ferric Oxide Red used besides medicines?
Outside pharmaceuticals, red iron oxide is widely used as:
- A pigment in paints, coatings, and plastics.
- A component in construction and ceramics.
- A coloring agent in various industrial and consumer products.
How do brands list it on labels?
In many cases, it appears in ingredient/excipient sections as “ferric oxide red,” “iron oxide red,” or by its color-index-style naming, depending on the labeling rules used for that product.
If you share where you saw it (for example, tablet/capsule label, topical product, or a supplement ingredient list), I can tell you what that specific listing likely means in practical terms.