Its small molecular weight (~400 Da) supports transdermal penetration through scalp skin
However, the lasting effects of these injections can vary significantly between individuals, influenced by factors such as overall health, the severity of the deficiency, and the bodys absorption capacity
Since your body already uses them for signaling purposes, breaking them down and recycling them poses no problem
I assume their lot has run out by now so this needs to be taken with a grain of salt
Correcting a deficiency can remove one biological contributor to low mood, and some people notice less irritability and a more positive outlook
Bulletin of Experimental Biology and Medicine .Read source Anisimov VN, Khavinson VKh, Provinciali M, et al