I thought my personal essay was totally lame. It was all about me and my boring life... why I decided to pursue pharmacy, what got me interested in pharmacy, the detours I took in life before I finally got on the right track to pharmacy. Like I said, lame and boring but I think they care more about your writing ability and your reason for pursuing pharmacy more than a riveting, unique, and interesting essay. I didn't know what to write at first either, but once you start, it's hard to stop! If you're really stuck, write about what is important to you... family, friends, motocross bike riding, whatever... say why it's important to you and what you have learnt from him/her/them/it. Whatever you do, don't write what you think they want to hear. Just be honest and write about you.
Hope this helps!