I think...in some studies, they used seroquel up to 300mgs at night in Bipolar I people (depressed)...with good results. that was the IR. The XR was approved later, of course...and after it was approved, all kinds of additional 'yay, seroquel!' data came out (seroquel for unipolar major depression, seroquel for Bipolar I maintenance, etc.).

i think it depends on what the prescriber has seen in practice, too. there's a lot that they see that will never make it into text books or FDA approvals, etc. a former psychiatrist once mentioned maybe trying seroquel in IR form at night -for me- , because I get so agitated while depressed. insurance coverage might play a role in ir/xr selection, too.

sorry about the hair loss w/ lamotrigine. i had it with depakote, but lamictal has been kind to me, in that regard. i hope things get better for you.