An anti-psychotic seems a little extreme for a child with anxiety. Also though not sure about the benydryl does he think it helps, and does he get side effects from that I mean I know I personally cannot stand benydryl because of how it makes me feel so you would want to make sure it doesn't cause him unpleasant side effects.

As far as meds go an as needed anti-anxiety med like a benzo for if a severe panic/anxiety attack arises...and supplement it with therapy, unless therapy alone seems effective but constantly taking an anti-psychotic or even benydryl probably could effect brain development and what not quite a lot. Therapy with maybe something for a severe panic attack where therapy tequniques and stuff don't work, also though there are calming herbs which can have less side effects than meds even chamomille and some other herbal tea is calming not sure your kid's much into drinking tea though. Just my thoughts can be taken or left.