On September 12, 2007, four pharmaceutical companies sent a letter to healthcare professionals informing them of revisions to the prescribing and warning information for products used in magnetic resonance imaging (MRI). The products, called gadolinium-based contrast agents, are approved by the Food and Drug Administration (FDA).

The labels were revised to include information about Nephrogenic Systemic Fibrosis (NSF), a potentially fatal medical condition. Reports have shown the use of the contrast agents increases the chance of a patient developing NSF.

The contrast agents that have the revised warning labels are:

• Magnevist
• MultiHance
• Omniscan
• OptiMARK
• ProHance

NSF, which was first identified in 1997, is a rare condition in which connective tissue in the skin becomes thickened, coarse, and hard. These symptoms can then lead to muscle contractions and joint immobility. NSF can also affect the lungs, liver, muscles and heart.

As of September 2007, the FDA received reports of more than 250 cases of NSF in patients who were given contrast agents. The agents were approved in the 1990s, with ProHance being approved as early as 1992. It is unknown why it has taken so long for the warning and prescribing information to be revised.

Source: “Important drug warning for gadolinium-based contrast agents,” Letter to Healthcare Professionals, United States Food and Drug Administration, September 12, 2007.