St. John's wort is for depression, not anxiety. There are natural remedies for anxiety, but since natural remedies are used in combination, not singly, it's probably best to see a naturopath to set up a plan, just as it's best to see a psychiatrist if treating it with pharmaceutical remedies. Any way you do it, therapy is an essential, though frustrating, part. Try reading the book Natural Highs by Hyla Cass, a psychiatrist at UCLA.