UMEM Educational Pearls

Title: Toxicity of Patches

Category: Toxicology

Keywords: transdermal, fentanyl, clonidine (PubMed Search)

Posted: 6/12/2008 by Fermin Barrueto (Updated: 12/26/2024)
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Trandermal Delivery Systems

Uses a gradient (high concentration drug in patch) and a matrix to facilitate transdermal absorption
Patch often contains up to 100x the amount of drug that is on the label (ex: fentanyl 100mcg/hr actually = 10 MILLIGRAMS of fentanyl in patch)
When prescribing the following will increase absorption: sweating, heat, swallowing the patch, trying to eat the gel in the patch
Fentanyl and clonidine are the two most lethal patches on the market in regards to toxicity.
Rarely needed in the ED, shouldn't be prescribed except in rare instances