Trace fentanyl/norfenatyl by contact alone?

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futureapppsy2

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One of my students is doing a clerkship at a substance abuse clinic, and mentioned that she had heard that fenantyl/norfenantyl traces (enough to show up on a screen) can show up even if a person hasn't used, via something like sharing a drink with someone who has recently used. My initial take was that this didn't sound legit, but I couldn't find anything in a quick lit search.

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Initial thought is not very likely.. but medical fentanyl is typically in a liquid form.. the kind abused by folks is often powdered.. I could see this powder getting everywhere rather easily and considering we are worried about micrograms I would say it is possible.
 
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seems very unlikely.

the cut off for fentanyl is typically 2 ng/ml.

one site I read says that a 25 mcg/hr patch at 24 hours will be anywhere from 0.3-1.2 ng/ml urine.
single dose studies of buccal fentanyl of 100-800 mcg suggests serum levels of 0.25-1.5 ng/ml. of course, one cannot correlate serum with urine levels.


oral half life for that small a dose is probably only 5 hours or so.

touching your lips on a tiny bit of fentanyl is not going to be as much fentanyl as a 25 mcg/hr patch that has been on an entire day, or 800 mcg of buccal fentanyl.


at the very least, I wouldn't prescribe to the person testing positive.

1. I'm guessing that the person would have to be sucking face with someone who is actively ingesting a fentanyl lozenge to test positive....
2. anyways, I wouldn't want to prescribe an opioid to someone who is positive for fentanyl on a prescreen...
 
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I agree concerning prescription fentanyl.. But we aren’t talking about medical fentanyl for the most part.. we are talking about iliicit extremely compact concentrated doses. Here’s a photo of 2000mcg of fentanyl. This is enough to do an entire CABG surgery for 4-8hours. This is the reason the cops that go into the houses where they are packaging this stuff wear masks and gloves.


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Agreed that contact with illicit fentanyl products can cause unintentional positives, but that exposure still is the same increase in risk for medical opioid therapy in my opinion.
 
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When in doubt don’t whip it out (rx pad)
 
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Heard all kinds of ridiculous things about positive tribe screens, they are all nonsense.

the urine does not lie
 
Do standard screens test for fentanyl or norfentanyl? The only way I can think of this happening(extremely unlikely) is if it's the former and there's residue on the patients hands at time of testing.
 
People also think that getting the COVID vaccine and peeing in the toilet will make the public sewage system full of viral DNA particles
 
I've said these phrases many times:

"It is your responsibility to make sure there are no illicit drugs in your system."
"If there are drugs in your system, that still poses an increased risk of overdose"
"If I have a test which shows drugs in your system and I continue to give you dangerous medications, I am at fault if anything happens."

Probably impossible, although who knows. Doesn't matter. Still positive.
 
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I defer to the urine 99% of the time and discontinue RX for abnormal urine. I've had one time where it was quite clear my lab screwed up and mixed samples/labels (entire profile on the urine made no sense: positive for norco not oxy, gaba not lyria, and the wrong antidepressant) and repeat urine was 100% appropriate.
 
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I've said these phrases many times:

"It is your responsibility to make sure there are no illicit drugs in your system."
"If there are drugs in your system, that still poses an increased risk of overdose"
"If I have a test which shows drugs in your system and I continue to give you dangerous medications, I am at fault if anything happens."

Probably impossible, although who knows. Doesn't matter. Still positive.
Exactly what I say. “Even if it’s not your fault” lol
 
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