It's just one of the multiple ways. There's other things as well from diet and supplements. I'm looking into dopamine stuff currently. Things like Maca, Shilajit, and Tongkat Ali. Stuff for GABA would be L-Theanine, Gotu Kola, Kava, and Rhodiola.
Serotonin isn't something PFS'ers have to worry about much. I have yet to see a neurotransmitter panel from someone with PFS that has low serotonin. Serotonin is stimulated to synthesize by estrogens, which we know aren't a problem since they usually run high(er) in us than normal people due to 5ar being methylated and Testosterone preferring aromatization into estradiol. It's almost always both GABA and Catecholamines. Bare in mind for the neurologist that they need to run a test for both Catecholamines and an Amino Acid Profile. Both together will show where the neurological issues are stemming from. Otherwise, you can test it yourself here:
ZRT Neuro Advanced Neurotransmitters Profile - www.canaryclub.org