Do anti-depressants also treat anxiety?

The reason I ask is that I forgot to take my Cipralex this morning and I almost had a panic attack in science, something that I just realized hasn't happened since I started taking Cipralex. In my defense, my teacher did tell us that we were all going to get brain tumors from our cell phones and the world was going to end (He's a tad pessimistic), but still. So...has the Cipralex helped with my anxiety problems too? Or is it just a fluke? I know they gave my cat anti-depressantst to treat her anxiety problems, but it might be differant for cats, so that's why I'm asking.