No, I haven't heard of this...
Serotonin in the body and blood stream does not cross the blood brain barrier. It has to be synthesized in the brain itself from tryptophan and B6. Over 90% of the serotonin in your body is NOT in the brain. Giving it by injection could cause flushing and other side effects.
It is possible the injection is a high dose B6 tryptophan combo to enable this synthesis.
I would find out more from your friend... what type of doctor, whether the "shot" is IV or not.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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