Thanks for the reply, Steve. I tried Rhodiola a couple of years back and had a really interesting reaction. I'm still not sure if it was because I took it on an empty stomach with a cup of coffee (my blood sugar was not well controlled at that time and I was having frequent hypoglycemic episodes) or if it was the herb itself, but I got really sweaty, dizzy and anxious (probably due to the symptoms) and was near passing out. I had to lie down on the cool floor for a while until it passed. After that I had a good day, but felt very removed and almost dissociated. Nothing could phase me, but I felt like I was in a clear haze, if that makes any sense. I actually have some rhodiola now (raw root) and could try making a tea with a really low dose to see what happens. My blood sugar is pretty stable now and I'm much more in tune with my body's reaction to things so I may consider it. Still, I feel a bit hesitant because of the previous reaction. It seems atypical, though, and I haven't heard of anyone having a similar experience.
EDIT: I should add that I take Siberian Ginseng (Eleuthero) during the day on a fairly regular basis but am looking to cycle it with something else to give myself a break every couple of weeks which I think is supposed to increase the efficacy of adaptogens. I really do love the Eleuthero though. No weird side effects or spaciness like with the Rhodiola and it helps my anxiety and motivation considerably.