- IgE-mediated (true anaphylaxis)
- Complement activation–related pseudoallergy (CARPA)
- Fishbane reaction
- Non_Fishbane CARPA
- Delayed (non-immediate) hypersensitivity
Hypersensitivity reactions” to IV iron refer to acute, systemic adverse events that occur during or shortly after infusion, usually within minutes. They range from mild, self-limited symptoms to life-threatening anaphylaxis.
Historically, these reactions were most common with high-molecular-weight iron dextran (no longer marketed in the U.S.) but can occur — rarely — with any formulation.
Modern preparations (iron sucrose, ferric carboxymaltose, ferumoxytol, ferric derisomaltose, etc.) have a very low rate of serious hypersensitivity (<1 per 200,000 doses for anaphylaxis).
