NBME 16 Induction of cytochrome P450 enzymes that activate acetaminophen to a hepatotoxic metabolite (NBME Answers)

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A 20-year-old man is brought to the physician ...
Induction of cytochrome P450 enzymes that activate acetaminophen to a hepatotoxic metabolite 🔍 / 📺 / 🌳 / 📖
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+10 upvote downvote
submitted by ∗hungrybox(1277)

ACUTE alcohol inhibits CYP → Increased bioavailability of acetominophen

CHRONIC alcohol induces CYP → Induction of cytochrome P450 enzymes that activate acetaminophen to a hepatotoxic metabolite

I got this wrong because I assumed chronic alcohol meant years and years. I guess a weekend will suffice?

Honestly, fuck this problem.

lfcdave182 Yeah fuck this question. 2-3 days of something would never be considered chronic in anything else. +6

pontiacfever Drink a lot for a week makes you a chronic alcoholic? +1

pontiacfever That means alcohol abuse = chronic alcoholism +2

skilledboyb Why would increased bioavailability of acetaminophen place the patient at increased risk of liver injury? What's dangerous about that? +

i_hate_it_here Metabolism of acetaminophen turns it into toxic metabolites (NAPQI) that inhibit glutathione in the liver forming toxic tissue products. FA2020 pg: 485 +3

+1 upvote downvote
submitted by ∗feliperamirez(45)

Acetaminophen is mainly glucuronidated and minimally metabolized to NAPQI by CYP 450 enzymes

Chronic alcohol consumption induces CYP 450, so more acetaminophen is metabolized to NAPQI

detayo Would this qualify as chronic alcohol though? +12

detayo Would this qualify as chronic alcohol though? +

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