FDA, Bayer issue letter to doctors about MRI agents.

Bayer Healthcare and FDA issued a "Dear Healthcare Professional" letter to notify of the addition of a BOXED WARNING and revisions to the WARNING section of the prescribing information for Gadolinium-based contrast agents used in Magnetic Resonance Imaging (MRI), the agency stated Sept. 28.

Gadolinium-based contrast agents are approved by FDA for use in MRI. Post-marketing reports show that the use of these agents increases the risk of the development of a serious medical condition called Nephrogenic Systemic Fibrosis (NSF), in patients with acute or chronic severe renal insufficiency and patients with renal dysfunction due to the hepatorenal syndrome or in the perioperative liver transplantation period.

NSF leads to excessive formation of connective tissue in the skin and internal organs. NSF is progressive and may be debilitating or fatal. FDA has received reports of over 250 cases of NSF after administration of gadolinium-based contrast agents, the agency reported

As a result of these NSF cases, the package inserts of all gadolinium-based contrast agents have been revised to include the following Boxed Warning and update to the Warnings section.

The MedWatch 2007 Safety Summary including a link to the Dear Healthcare Professional letter and the revised labeling is available at:: http://www.fda.gov/medwatch/safety/2007/safety07.h tm#Gadolinium