deferoxamine
Meaning of deferoxamine: The body has no way to excrete surplus iron, so anyone transfused repeatedly needs a drug to carry it out for them.
Definition of deferoxamine
Deferoxamine is a drug that binds iron in the body and carries it out in the urine, used for iron overload and for acute iron poisoning. It was isolated from soil bacteria, which make it to capture iron from their surroundings, and it clamps a single iron atom inside a tight cage. It is barely absorbed from the gut, so it is given by slow infusion under the skin or into a vein.
Why does the body need help removing iron?
There is no route out. The body absorbs iron sparingly and recycles nearly all of it, because iron is scarce in most diets, but it has no mechanism for excreting a surplus. Small amounts leave in shed skin and gut lining and in any bleeding, and that is all. Someone receiving regular blood transfusions takes in iron with every unit and cannot dispose of it. The excess piles up in the liver, the heart and the hormone glands, where unbound iron drives reactions that damage tissue. Deferoxamine acts as a chelating agent: it grips one iron atom at several points at once, forming a stable package the kidneys filter into the urine, which it tints orange or reddish brown.
Why is it given as a slow drip?
Two properties force it. The drug is broken down in the gut and barely absorbed there, so a tablet achieves nothing. And it vanishes from the blood within minutes, so a quick injection binds only whatever iron is circulating at that instant. Removing a useful quantity means holding a low concentration in the blood for hours, traditionally through a small pump worn overnight several nights a week. That burden explains why doses are so often missed, and why chelators that can be swallowed have taken over much of long-term use. Deferoxamine remains a mainstay for acute iron poisoning, given into a vein.
What is it not?
It is not an anticancer drug. Descriptions listing it as therapy for neuroblastoma overstate what has been shown. Starving cells of iron does slow the enzyme that supplies building blocks for new DNA, and the idea has been tested in tumors, but it stays investigational rather than established. Its recognized harms follow from the same stripping action: hearing loss at high pitches, changes in vision, and slowed bone growth with prolonged use in children. Infused quickly it drops blood pressure. Certain bacteria and molds can feed on the iron package the drug forms, so infection with Yersinia species and with the molds causing mucormycosis is a known hazard during treatment.
Also known as
Used in a sentence
Deferoxamine was infused overnight to manage transfusional iron overload.
Good to know
Deferoxamine is an iron chelator rather than an anticancer drug, and the iron complex it forms can be used as a nutrient by Yersinia species and by the molds causing mucormycosis, so infection with these organisms is a recognized hazard of treatment.