Which statement about acetaminophen is true?

Which statement about acetaminophen is true?

• A. Hepatotoxicity (overdose risk)
• B. Ototoxicity
• C. Hypertension
• D. Hypokalemia

Answer: (A)

Acetaminophen can cause liver injury in a dose-dependent way because it is metabolized to a toxic compound, NAPQI, by the liver’s cytochrome P450 system. Under normal dosing, most of the drug is processed safely through sulfate and glucuronide conjugation and eliminated. A small amount is oxidized to NAPQI, but this reactive metabolite is normally neutralized by glutathione. When overdose occurs, or when glutathione stores are depleted (as in malnutrition, fasting, or chronic alcohol use which induces the enzymes that produce NAPQI), NAPQI accumulates and binds to hepatocyte proteins, leading to hepatocellular injury and potential liver failure. This is why the overdose risk is the important, true statement about acetaminophen. An antidote, N-acetylcysteine, helps by replenishing glutathione and scavenging NAPQI if given early enough. Ototoxicity is not a typical effect of acetaminophen; it’s more associated with certain other drugs (like high-dose aspirin or some antibiotics and loop diuretics). Hypertension and hypokalemia are not characteristic adverse effects of acetaminophen.

Acetaminophen can cause liver injury in a dose-dependent way because it is metabolized to a toxic compound, NAPQI, by the liver’s cytochrome P450 system. Under normal dosing, most of the drug is processed safely through sulfate and glucuronide conjugation and eliminated. A small amount is oxidized to NAPQI, but this reactive metabolite is normally neutralized by glutathione. When overdose occurs, or when glutathione stores are depleted (as in malnutrition, fasting, or chronic alcohol use which induces the enzymes that produce NAPQI), NAPQI accumulates and binds to hepatocyte proteins, leading to hepatocellular injury and potential liver failure. This is why the overdose risk is the important, true statement about acetaminophen. An antidote, N-acetylcysteine, helps by replenishing glutathione and scavenging NAPQI if given early enough.

Ototoxicity is not a typical effect of acetaminophen; it’s more associated with certain other drugs (like high-dose aspirin or some antibiotics and loop diuretics). Hypertension and hypokalemia are not characteristic adverse effects of acetaminophen.