Which of the following is NOT listed as a secondary target of ketamine?

Which of the following is NOT listed as a secondary target of ketamine?

• A. Opioid Receptor
• B. MAO
• C. Serotonin Receptor
• D. NMDA Receptor

Answer: (D)

Ketamine’s primary mechanism is NMDA receptor antagonism, which drives its dissociative anesthesia and analgesia. Because this receptor is the main site of action, it is not considered a secondary target. Ketamine also interacts with other systems that contribute to its effects—such as some activity at opioid receptors and modulation of monoaminergic pathways (serotonin, norepinephrine, dopamine)—which can influence analgesia and mood. These are considered secondary targets that help shape the overall pharmacologic profile, rather than the primary mechanism. Therefore, the receptor not listed as a secondary target is the NMDA receptor, since it is the primary receptor ketamine blocks.

Ketamine’s primary mechanism is NMDA receptor antagonism, which drives its dissociative anesthesia and analgesia. Because this receptor is the main site of action, it is not considered a secondary target. Ketamine also interacts with other systems that contribute to its effects—such as some activity at opioid receptors and modulation of monoaminergic pathways (serotonin, norepinephrine, dopamine)—which can influence analgesia and mood. These are considered secondary targets that help shape the overall pharmacologic profile, rather than the primary mechanism. Therefore, the receptor not listed as a secondary target is the NMDA receptor, since it is the primary receptor ketamine blocks.