What are people's views on St John's Wort?

[A human Being]

I've been experiencing a lot of anxiety at times recently and I had an especially difficult day today after a fairly unpleasant encounter with a paranoid schizophrenic (he's the cousin of a friend I was visiting, I had no idea he'd be there). I didn't hang around any longer than I had to, but it still shook me up pretty badly and it brought a lot of anxiety right to the surface. Anyway, so I went to the pharmacy and asked what the lady recommended for anxiety and she suggested St John's Wort (she also suggested a trip to my GP if that doesn't do the trip, but I'll see how it goes - I want to avoid prescription drugs if I possibly can, anyway), so I'm just interested to hear of people's experiences with it. How effective was it for you? How soon did it take you to notice a difference?