Hi Ellycat,
I was prescribed mirtazapine a couple of months ago. The first thing I noticed was that they put me to sleep, I mean really put me to sleep. I took my first dose at around 8.30pm and I was asleep on top of my bed, still fully dressed, with the light on within about 20 minutes. And I didn't wake up until about 10 the next morning. The sleep was actually really good for me once I made sure I was ready for bed before I took them and that effect is supposed to derease a bit once you get up to a higher dose. I had to stop taking them after a couple of weeks though because I kept blacking out and fainted a couple of times when I stood up which made actually doing anything difficult. Apparently this doesn't happen that often or not as severely anyway. Anyway, I wasn't on them long enough to get any antidepressant effect. Sorry, not being very helpful am I?
Good luck with them, I hope they work for you