B2Y
I've not tried the med your faced with, but I am really sensitive to meds.
I started Namenda last week, 5mg, this week it was to be 5mg 2x day. But I'm only doing 1/2 of 5mg 2x day, because I was knocked out, barely functioning exhausted last week. I'm going to take it super slow.
When I started Lexapro 10mg last summer, it took 6 weeks to get to a whole 10mg.
If you can take a 1/4 or 1/2 and see how you feel. Best of luck to you.