IV Iron Treatments Linked To Anaphylaxis Risk: Study

Injectafer fared better than the competing IV iron supplements, Dexiron and Feraheme, which were three to eight times more likely to cause anaphylaxis.

Side effects of intravenous iron treatments, like Injectafer, Dexiron and Feraheme, may include a risk of serious and life-threatening allergic reactions, according to the findings of a new study.

In findings published this week in the Annals of Internal Medicine, researchers from the Rutgers University note that the overall risk of anaphylaxis from iron IV supplementation is low, but some products have notably higher rates than their competitors, particularly Dexiron and Feraheme.

Iron IV infusions are often given to adults with anemia, who are not able to be treated with an oral iron supplement.

In this latest study, researchers compared the risks for anaphylaxis among several, frequently used, IV iron products. They looked at Medicare fee-for-service data from between July 2013 and December 2018 involving older adults who suffered anaphylaxis on the first day of IV iron administration.

According to the findings, there were 9.8 cases of anaphylaxis for every 10,000 first administrations linked to Dexiron (iron dextran); and four cases per 10,000 involving Feraheme (ferumoxytol). That compares to 1.2 cases per 10,000 first administrations with iron sucrose, which was used as the baseline referent category. Injectafer, one of the most widely used IV iron drugs, only had 0.8 cases per 10,000, giving it the lowest rate of anaphylaxis out of all the drugs tested, but the iron infusion did still carry a risk.

“The rates of anaphylaxis were very low with all IV iron products but were 3- to 8-fold greater for iron dextran and ferumoxytol than for iron sucrose,” the researchers determined.

Injectafer Blood Phosphorus Concerns

The findings come amid increasing concerns about the side effects of Injectafer (ferric carboxymaltose), which was introduced in 2013 and has been linked to reports of severe hypophosphatemia (HPP), which is a medical condition associated with drops in blood phosphate levels, increasing the risk of severe health complications like cardiac arrest, respiratory failure and death.

There are now a growing number of Injectafer lawsuits being pursued by individuals who experienced complications after an iron infusion, alleging that the drug makers failed to adequately warn about the risk and importance of blood phosphate testing after treatments, which can result in a serious and life-threatening medical emergency.

Plaintiffs pursuing lawsuits over the iron infusions allege the drug makers knew or should have known about the risks associated with their treatment, and placed the desire for profits before patient safety by minimizing the Injectafer FDA label warnings, previously suggesting that serum phosphate drops were “asymptomatic” or “transient.”

While updated warnings were provided in February 2020, recommending doctors monitor serum phosphate levels among patients at risk of problems or requiring repeat courses of the iron infusion, a growing number of experts now suggest doctors should be encouraged to test blood phosphate levels for all patients.

Severe HPP caused by Injectafer has also been linked to reports of bone fractures, heart rhythm problems, kidney problems and a host of other ailments caused by persistent and drops in blood phosphorous levels.