Risk of Burns during MRI Scans from some Transdermal Drug Patches

The FDA announced on March 5^th, 2009 that transdermal patches containing aluminum or other metals in their backing may cause skin burns to the patched-area during MRI scans.¹  Roughly 60 different transdermal patch products are sold in the United States, as estimated by the FDA.²  Transdermal patches allow slow, steady delivery of drugs through the skin and offer an alternative route of administration to oral medications.  The first trandermal patch approved by the FDA was scopolamine, which was approved in 1979.³  Since then, many more transdermal patches have been approved such as those containing nicotine for smoking cessation, pain controlling patches like fentanyl patches, and even patches containing estrogens for birth control or menopause.

 

Transdermal patches often consist of several layers, including an impermeable backing.²  It is in this backing that some patches contain aluminum or other metals.¹  If a patient is wearing a metal-containing patch during an MRI, it can overheat and result in skin burns in the area where the patch has been applied.¹  While some transdermal patch products do contain a warning about wearing during an MRI, some do not.¹  The FDA is currently reviewing labeling and patch composition to identify which patches need new labeling and warnings about this risk.¹  The FDA hopes to also include a warning directly on the patch.²

 

Patients should be instructed to tell their doctor referring them for an MRI if they use a patch and what it is.¹  Doctors should guide patients on the proper removal/replacement of patches during an MRI.¹  The FDA has identified some key products where updated labeling and warnings may be needed: Catapres TTS (Clonidine), Neupro (Rotigotine), Lidopel (lidocaine HCL and epinephrine), Synera (lidocaine and tetracain), Transderm-Scop (scopolamine), Prostep (nicotine), Habitrol (nicotine), Nicotrol TD (nicotine), Androderm (testosterone), Fentanyl, and Salonpas Power Plus (methyl salicylate and menthol).¹

 

Lindsey Koliscak, PharmD Candidate

 

References:

 

1. FDA Staff.  FDA Public Health Advisory: Risk of Burns during MRI Scans from Transdermal Drug Patches with Metallic Backings.  [March 5, 2009].  U.S. Food and Drug Administration.  Available at www.fda.gov/cder/drug/advisory/transdermalpatch.htm.
2. Traynor K.  FDA Warns of MRI Burn Risk for Transdermal Patches.  [March 5, 2009].  American Society of Health-System Pharmacists.  Available at www.ashp.org/import/news/ HealthSystemPharmacyNews/newsarticle.aspx?id=304.
3. Segal M.  Patches, Pumps and Timed Release: New Ways to Deliver Drugs.  U.S. Food and Drug Administration.  Available at www.fda.gov/bbs/topics/consumer/CON00112.html.