Found out about this in a ejaculatory ahedondia board
en.wikipedia.org/wiki/Picamilon - perhaps its better then some of the other gaba related supps.
Theanine is also an option
People with mental sides and depression may also benefit. Many experiments in Russia have shown it to restore GABAa receptors following induced depressive states and improve brain blood flow.
E.g.
ncbi.nlm.nih.gov/pubmed/20821973
ncbi.nlm.nih.gov/pubmed/19803364
ncbi.nlm.nih.gov/pubmed/16845932
There are many more if you search on pubmed.