Pharmacology Basics Flashcards

To use the Rumack-Matthew nomogram, the acetaminophen level should be drawn no earlier than how long after an acute ingestion?

Answer: 4 hours

The nomogram is valid from 4 hours after ingestion, once absorption is mostly complete.

What is the antidote for acetaminophen overdose?

Answer: N-acetylcysteine

N-acetylcysteine refills glutathione, which neutralizes the toxic metabolite NAPQI.

Which urine metabolite is the main target of cocaine drug screens?

Answer: Benzoylecgonine

Benzoylecgonine is the major cocaine metabolite and stays in urine longer than the parent drug.

Urine immunoassays for marijuana use usually detect which compound?

Answer: THC-COOH (11-nor-9-carboxy-THC)

THC-COOH is the main inactive metabolite excreted in urine.

A patient has both an increased osmolal gap and an increased anion gap metabolic acidosis after drinking windshield washer fluid. Which antidote is indicated?

Answer: Fomepizole

Fomepizole blocks alcohol dehydrogenase, which stops methanol from being converted to toxic formic acid.

Which acid-base pattern is typical of an adult salicylate overdose?

Answer: Respiratory alkalosis with metabolic acidosis

Salicylates stimulate the respiratory center first, then cause an anion gap metabolic acidosis.

What is the main purpose of chain-of-custody documentation for forensic drug testing?

Answer: To document who handled the specimen at every step so it holds up legally

Chain of custody proves the specimen's integrity and identity for legal purposes.