Most BRICK that we see in the States is sativa from warm-weather areas such as Mexico.
Panic attacks from smoking weed aren't uncommon. The racy sativa high simply doesn't agree with everyone; personally, I avoid it as I already suffer from anxiety and it will on occasion put me over the edge where I just feel really antsy and uncomfortable. I've never had a full-blown panic attack from smoking brick, but come close. Choose your weed to match your needs. If you are prone to panic or anxiety, look into more calming lines such as the Afghanis.