American Regent has issued new precautionary measures for preventing anaphylactic-type reactions when administering Dexferrum (iron dextran injection).

An updated boxed warning for Dexferrum now says that a test dose should be administered before giving the first therapeutic dose. A test dose of 0.5 mL should be given gradually, over at least five minutes. Although reactions are usually seen within a few minutes, patients should be observed for at least an hour after the test dose.

The boxed warning also points out that some patients have experienced fatal reactions after receiving the test dose. Others have died after tolerating the test dose and then receiving a therapeutic dose. Because of this, patients should be observed for signs and symptoms of anaphylactic-type reactions every time Dexferrum is administered, and resuscitation equipment and trained personnel should be readily available.

The company’s letter says that patients with a history of drug allergy or multiple drug allergies, and patients receiving ACE inhibitors, may have a higher risk of anaphylactic-type reactions. It also reminds clinicians that Dexferrum should only be used for patients whose iron deficiency isn’t amenable to oral iron therapy.