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Wednesday, September 2, 2026

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Science · Wednesday, September 2, 2026

FDA adds boxed warning to Injectafer (ferric carboxymaltose) for symptomatic hypophosphatemia

The File desk · Sep 2, 2026, 1:58 PM UTC

Status

Confirmed from an FDA Drug Safety Communication dated Sept. 1, 2026.

On Sept. 1, 2026, FDA said it approved revisions to the labeling for ferric carboxymaltose injection (currently marketed as Injectafer) that add a boxed warning, the agency’s most prominent safety warning, describing the risk of symptomatic hypophosphatemia and recommending phosphate monitoring in patients at risk and in any patient who receives a repeat course of therapy within three months of the prior course.

FDA wrote: “The Food and Drug Administration has approved revisions to the labeling for ferric carboxymaltose injection (currently marketed as Injectafer) that adds a boxed warning, the agency’s most prominent safety warning.”

The Sept. 1, 2026, Drug Safety Communication says the boxed warning describes the risk for symptomatic hypophosphatemia associated with ferric carboxymaltose injection and recommends phosphate monitoring in patients at risk of hypophosphatemia and in any patient who receives a repeat course of therapy within three months of the prior course. FDA said it had previously added and strengthened warnings in 2020, 2023, and 2025, and that symptomatic hypophosphatemia continues to be reported.

What is still unknown or disputed

Primary sources

Every claim in this story is drawn from the documents below. If a fetch failed, that is recorded on the card.

  1. Source 1

    FDA Adds Boxed Warning to Labeling for Ferric Carboxymaltose Injection (Injectafer) to Describe Risk of Low Phosphate Levels

    U.S. Food and Drug Administration · September 1, 2026

    The Food and Drug Administration has approved revisions to the labeling for ferric carboxymaltose injection (currently marketed as Injectafer) that adds a boxed warning, the agency’s most prominent safety warning. This boxed warning describes the risk for symptomatic hypophosphatemia (low levels of phosphate in the blood) associated with ferric carboxymaltose injection and recommends phosphate monitoring in patients at risk of hypophosphatemia and in any patient who receives a repeat course of therapy within three months of the prior course.

    https://www.fda.gov/drugs/drug-safety-communications/fda-adds-boxed-warning-labeling-ferric-carboxymaltose-injection-injectafer-describe-risk-low