Toxicology and antidotes: thiamine before glucose: practice question

A Pharmacology question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Pharmacology · Toxicology and antidotes: thiamine before glucose

Sample item

A malnourished man with chronic alcohol use is brought in confused, with nystagmus, ataxia and a blood glucose of 40 mg/dL. What is the correct treatment sequence?

AIntravenous thiamine before or with dextroseBIntravenous naloxone then dextroseCOral multivitamin with dextrose withheldDIntravenous dextrose first, thiamine a day later

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

A. Intravenous thiamine before or with dextrose

Glucose metabolism consumes thiamine, so dextrose given alone to a thiamine-deficient patient can precipitate or worsen Wernicke encephalopathy. Thiamine should be given first or together with dextrose, so hypoglycaemia is treated without delay and the brain is protected.

Option by option

A. Intravenous thiamine before or with dextrose (correct)
Correct. Thiamine is given first or with glucose to avoid precipitating Wernicke encephalopathy.
B. Intravenous naloxone then dextrose
Naloxone treats opioid toxicity and does not address the thiamine deficit.
C. Oral multivitamin with dextrose withheld
Withholding dextrose in hypoglycaemia is dangerous, and oral vitamins are inadequate.
D. Intravenous dextrose first, thiamine a day later
Delaying thiamine by a day risks worsening Wernicke encephalopathy once glucose is metabolised.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Pharmacology question

What is the answer to this Pharmacology question?

The best answer is A, Intravenous thiamine before or with dextrose. Glucose metabolism consumes thiamine, so dextrose given alone to a thiamine-deficient patient can precipitate or worsen Wernicke encephalopathy.

Why is "Intravenous naloxone then dextrose" not the answer?

Naloxone treats opioid toxicity and does not address the thiamine deficit.

Why is "Oral multivitamin with dextrose withheld" not the answer?

Withholding dextrose in hypoglycaemia is dangerous, and oral vitamins are inadequate.

Why is "Intravenous dextrose first, thiamine a day later" not the answer?

Delaying thiamine by a day risks worsening Wernicke encephalopathy once glucose is metabolised.

What concept does this question test?

It tests Toxicology and antidotes: thiamine before glucose in Pharmacology. Thiamine should be given first or together with dextrose, so hypoglycaemia is treated without delay and the brain is protected.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Toxicology and antidotes: thiamine before glucose?

Learn drugs as classes, then the exception in each class that an examiner would pick. Then use the flashcards and the other Pharmacology questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.