FDA requests warning for MR contrast agents.

The U.S. Food and Drug Administration has asked manufacturers to include a new boxed warning on the product labeling of all gadolinium-based magnetic resonance contrast agents.

The requested warning would state that patients with severe kidney insufficiency who receive gadolinium-based agents are at risk for developing a debilitating and potentially fatal disease known as nephrogenic systemic fibrosis, or NSF. In addition, the warning should state that patients just before or just after liver transplantation or those with chronic liver disease also are at risk for developing NSF if they are experiencing kidney insufficiency of any severity.

Besides Omniscan and Magnevist, the FDA has approved three other gadolinium-based contrast agents for use in the United States, including OptiMARK, MultiHance and Prohance. Patients should undergo screening for kidney problems prior to receiving any of these contrast agents. The recommended dose should not be exceeded, and enough time should elapse to ensure that a dose has been eliminated from the body before the agent is used again.

There have been no reports of NSF among patients with normal kidney function or those with mild-to-moderate kidney insufficiency.