Well, it worked for me. Dosage matters and I had to take it religiously for several months, but I'm back to normal now.
Will it work for everyone? probably not. Is it worth a shot? I think so. It's widely available and cheap. There's quite a bit of research regarding it's use in treating cold sores (herpes virus). Same goes for high dose "stress formula" B-complex. Might not work for everyone, but worth exploring.