Hi - never heard that about GABA. I actually had low levels of testosterone anyway, but perhaps I will get tested to check out my levels. It has not made my heart race though.
Melatonin is not advisable for people with autoimmune diseases.
So far, GABA is the only thing that works well for me. I just ordered some valerian root from a place that I was told produces it in such a way that makes it more effective. I was told by an herbalist that most valerian products actually can stimulate you because of poor preparation. I'll give it a try. It's from Herb Pharm in case anyone is interested.