Some novel classes of hypnotics that come to mind are melotonin receptor agonists and orexin antagonists. I don't know how available they are yet though. I haven't looked into it, but maybe there are adenosine agonists available. Maybe you could take one of those, along with a vasoconstrictor to counteract the headaches and low blood pressure. Have you tried other non selective antagonist drugs like TCAs such as amitryptiline? You could probably find one with less 5-HT2 affinity than mirtazapine. Also, IME trazodone works nearly as well as mirtazapine but less side effects.
BTW we should combine our knowledge of difference classes of hypnotics into an article, because I've searched for a comprehensive article like this in the past but all I could were articles that covered little more than GABAergics, antihistamines, and 5-HT antagonists. I'll pitch in all my knowledge. My motivation and energy levels are pretty low after quitting amphetamine, but I'll do this when I have more energy. Often times when reading about pharmacology related things, I come across a substance with a novel mechanism of action, but I forget the name of it, so its good to save the info somewhere.
Edited by FrogWarrior, 09 December 2013 - 08:55 PM.