Well, I can't tell you what it is, euphy. But I certainly know what you're referring to. I don't tend to have so much trouble with this now because I pretty-much just keep to myself. But in years past when I was working & out in public, I would have episodes where I'd get all pumped up & I would say or do things that later on would make me cringe.
I don't know if this could be considered a form of mania or sort-of an intermittent form of Narcissism, or something else. I guess that is something I would have to leave to the mental health professionals to determine. One thing that certainly helps is to maintain an awareness of what you're feeling & doing & to wait, even for a second or two, before responding in situations that are likely to trigger this loss of conscience. This is essentially the objective behind the practice of mindfulness.