The tachycardia seen with meperidine is attributed to which structural property?

The tachycardia seen with meperidine is attributed to which structural property?

• A. Mu Receptor Agonism
• B. Delta Receptor Agonism
• C. Serotonin Reuptake Inhibition
• D. Atropine-Like Structural Effect

Answer: (D)

Tachycardia with meperidine stems from its atropine-like antimuscarinic properties that arise from its chemical structure. By blocking muscarinic receptors in the heart, parasympathetic (vagal) influence is reduced, allowing the heart rate to rise. This antimuscarinic effect explains the tachycardia, and it sets meperidine apart from other opioids whose main actions are mu receptor–mediated analgesia and often do not cause this vagal withdrawal. Delta receptor agonism isn’t involved here, and while serotonin reuptake inhibition can occur with some analgesics, it doesn’t account for the tachycardia seen with meperidine.

Tachycardia with meperidine stems from its atropine-like antimuscarinic properties that arise from its chemical structure. By blocking muscarinic receptors in the heart, parasympathetic (vagal) influence is reduced, allowing the heart rate to rise. This antimuscarinic effect explains the tachycardia, and it sets meperidine apart from other opioids whose main actions are mu receptor–mediated analgesia and often do not cause this vagal withdrawal. Delta receptor agonism isn’t involved here, and while serotonin reuptake inhibition can occur with some analgesics, it doesn’t account for the tachycardia seen with meperidine.