If a patient has chronic pain due to amplified nociceptor signals at the spinal cord, which pharmacological intervention would best reduce pain via descending modulation?

💡 Explanation

Serotonin reuptake inhibitors enhance serotonin levels, which activate descending inhibitory pathways that modulate pain signals in the spinal cord because serotonin stimulates interneurons releasing enkephalins, inhibiting substance P release. Therefore, pain is reduced via descending modulation rather than direct receptor antagonism or local anesthetics.

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