Fever & Fentanyl patch comes with a catch!

I call my thumb a game-changer – it literally helps me swipe up from my Call of Duty mobile app and swap to goat simulator game on my iPhone. Am I funny or am I hilarious ? 😁 Fentanyl patches have been around a while and when introduced were hailed as game-changers in pain management. Fentanyl is also available as a lollipop for people on chronic use ! Over time they have been associated with many caveats, adverse effects and some horrible tragedies like this child who ate his mothers fentanyl patch while lying on her for a nap !

In other words, treat a patch with mad respect & caution – always ask if your admitted patients are wearing medical patches since they might forget to report it on their list of home meds. One caveat not very well regarded or as known to clinicians is the effect of skin temperature on fentanyl absorption from patches. This 2020 case report showed how fever resulted in encephalopathy in an elderly lady wearing a fentanyl patch, which reversed with Naloxone. The same article notes that a 3-degree rise (Celsius) of skin temperature can increase fentanyl absorption by 25% ! The official Duragesic drug label submitted to FDA states – “serum fentanyl concentrations could theoretically increase by approximately one-third for patients with a body temperature of 40°C (104°F) due to temperature-dependent increases in fentanyl released from the system
and increased skin permeability‘ . However, remember it’s not just fever, any external heat for that matter too – This case report from 1998 highlighted fentanyl toxicity in a man attending summer camp wearing a patch. This one from 2003 has case-reports on heating pads and warm blankets causing patch-related fentanyl overdose. In such cases removing the patch will result in a slow drift of fentanyl levels to 50% by 24 hours. May need reversal with naloxone, taking away heat and controlling temperatures aggressively.

So again…respect those fentanyl patches 🙂 A patient with fever and excessively drowsy might be on a fentanyl-trip from her transdermal fentanyl patch. Always warn the patient when you start them on a new patch. On a side-note, heard about wooden chest syndrome from Fentanyl ?