The best idea is no meds for panic or anxiety, mostly because it's a trial and error thing. You'd have to go through a long list of different meds to find one that does work for you, in particular, because everyone's biochemistry is different.

The other reason is that if SHTF, there's a chance you could be dependent on a med and then have to go off it abruptly, which is a distinct no-no...withdrawal is brutal, from what I've read and heard.

What works for me is keeping busy, being creative (making stuff to sell or give as gifts), keeping a journal, making a website, anything that challenges your abilities.
Just my two cents.