why are serotonin–norepinephrine reuptake inhibitors used for anxiety when norepinephrine causes anxiety?

Question

why are serotonin–norepinephrine reuptake inhibitors used for anxiety when norepinephrine causes anxiety?

In: 119

Answer 1

Outside of serotonin, since that is a bit more complicated, the norepinephrine aspect lies solely with the presynaptic a2 receptor. That is the key. Faulty signaling can lead to that receptor becoming desensitized, or downregulated. The extra NE helps make sure that receptor is saturated, begins to upregulate, and eventually return to normalcy. The presynaptic a2 receptor is the negative feedback loop mechanism of NE, so basically your entire fight or flight response. When NE hits it, it causes further NE release to be stopped, it basically ends the fight or flight response.