Ferumoxytol: risk of serious hypersensitivity reactions—contraindicated if any drug allergy; administer via infusion

New recommendations are being introduced to minimise the risk of serious hypersensitivity reactions with ferumoxytol.


The licence-holder of ferumoxytol (Rienso) has voluntarily withdrawn it from the UK market. Please see the drug recall sent on 12 March 2015.

Article date: September 2014

Hypersensitivity reactions are known to occur rarely with all intravenous (IV) iron products and may be life-threatening. Recommendations to manage and minimise this risk were strengthened in 2013 following an EU review (see Drug Safety Update article from August 2013).

Risk of hypersensitivity reactions with ferumoxytol

Ferumoxytol (Rienso) was approved in the EU in June 2012 for the IV treatment of iron deficiency anaemia in adults with chronic kidney disease.

The European Medicines Agency has re-evaluated the benefits and risks of ferumoxytol. The evaluation focused on the cumulative reports of serious hypersensitivity reactions—including life-threatening and fatal anaphylactic reactions—to ferumoxytol since it was first approved for use in the USA in 2009 (see Drug Safety Update article from June 2014). Many of the patients who had a life-threatening or fatal anaphylactic reaction also had a known history of drug allergy to a non-iron product (eg, an antibiotic). New recommendations for ferumoxytol are being introduced as a result of this re-evaluation:

Advice for healthcare professionals


  • Ferumoxytol is now contraindicated in patients with any known history of drug allergy, including hypersensitivity to other parenteral iron products.
  • As with all IV iron products, the risk of hypersensitivity is increased in patients with immune or inflammatory conditions (eg, systemic lupus erythematosus, rheumatoid arthritis) and in patients with a history of severe asthma, eczema, or other atopic allergy. In these patients, ferumoxytol should only be used if the benefits are clearly judged to outweigh the risks.


  • Ferumoxytol should only be administered as an intravenous infusion, in 50 to 250 ml of sterile 0.9% sodium chloride or sterile 5% glucose, and over a minimum period of 15 minutes. Do not administer by injection.
  • Place patients in a reclining or semi-reclining position during the ferumoxytol infusion and for at least 30 minutes thereafter.
  • Carefully monitor patients for signs and symptoms of hypersensitivity reactions, including monitoring of blood pressure and pulse, during and for at least 30 minutes after the infusion.
  • As with all IV iron products, ferumoxytol should only be administered when resuscitation facilities and staff trained to evaluate and manage anaphylactic or anaphylactoid reactions are immediately available.

Information for patients

  • Tell patients to immediately inform their healthcare practitioner if they start to feel unwell during or after their ferumoxytol infusion.
  • As with all IV iron products, patients should be informed of the risk and potential seriousness of a hypersensitivity reaction before every administration of ferumoxytol.

Reporting of suspected adverse drug reactions

  • Please continue to report suspected adverse reactions to any IV iron product, including ferumoxytol, to us on a Yellow Card. Please include the name of the specific product administered (www.mhra.gov.uk/yellowcard).

Further information

Letter sent to healthcare professionals in August 2014


Article citation: Drug Safety Update volume 8 issue 2, September 2014: A1

Published 11 December 2014