Thanks, Lara, for your response and the article links. Unfortunately, it must have been something other than the Mg Threonate that led to that one blissful night of sleep. That and melatonin are still all I'm taking, but I'm back to taking too long to fall asleep and waking multiple times. I am still fairly functional at this point and my mood is much better than it usually would be after this many weeks since I quit the Ambien, which is somewhat surprising, but I can tell my levels of concentration and my mental processing speed are both way down. Oh, well. I'm sure the extra Mg is helping, so I'm sticking with it.