SBA — Single Best Answer · Review
Question 462
Pharmacology → General
Classification
Question
SSBAQuestion Header
A neonate develops respiratory depression following maternal administration of an opioid analgesic. Which drug most directly reverses the opioid effect?
Question Stem
Select the single best answer.
Options
A
Flumazenil
B
Naloxone
C
Phentolamine
D
Metolazone
E
Moclobemide
Explanation
Centrally acting opioids cross the placenta and may cause fetal or neonatal respiratory depression. This respiratory depression can be reversed by naloxone. Flumazenil is instead described as an antagonist of benzodiazepine effects.
Option Validity
A) Flumazenil antagonises benzodiazepine effects; it is not the opioid antagonist identified for reversal of opioid-induced neonatal respiratory depression.
C) Phentolamine is an alpha-adrenoceptor blocker used in the context of the tyramine-MAOI hypertensive reaction.
D) Metolazone is a thiazide-type diuretic and does not reverse opioid respiratory depression.
E) Moclobemide is a reversible inhibitor of MAO-A and is not an opioid antagonist.
Further Reading
Saxena R. Textbook for MRCOG-1. Chapter 12: Pharmacology. Analgesics, pp.346–347.