Neostigmine

Question 1

What is the mechanism of action of neostigmine?

Answer 1

Acetylcholinesterase inhibitor

• Competes with acetylcholine for binding sites on acetylcholinesterase → increased concentration of acetylocholine within the synaptic cleft

_{Apex Unit 5: Pharmacology 2 - NMB Reversal Agents
Nagelhout (7th ed.), p. 174 - Table 12.11}

Question 2

What is the pharmacologic category/class of neostigmine?

Answer 2

• Acetylcholinesterase inhibitor

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2}

Question 3

What is the dosage range of neostigmine for reversal of neuromuscular blockade?

Answer 3

• 20-70 mcg/kg (0.02-0.07 mg/kg)

MAX dose = 0.07 mg/kg or 5 mg (whichever is less)

_{Nagelhout (7th ed.), p. 174 - Table 12.11}

Question 4

What is the onset of action of neostigmine?

Answer 4

• 5-15 minutes

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2
Nagelhout (7th ed.), p. 174 - Table 12.11}

Question 5

To avoid postoperative residual neuromuscular blockade or prolonged time to full recovery, neostigmine administration should be timed when TOF exhibits recovery of __________ twitches

Answer 5

• 3/4 or 4/4

When administered at TOF 2/4, recovery can take as long as 49 minutes

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2
Stoelting’s Pharmacology (5th), pp. 335-336}

Question 6

What is the duration of action for neostigmine?

Answer 6

• 30-60 minutes

_{Anesthesia Guidebook - Episode 18: Anesthesia Top Drawer Run Down - Part 2}