Patterns of imbalance: Overbearing or intolerant behavior; overenthusiasm or extreme fanaticism; nervous exhaustion from overstriving.
Vervain soul types naturally possesses strong forces of passionate idealism. They give themselves fully and completely to the work or cause in which they believe. However, they can become so convinced of the rightness and urgency of their beliefs that their natural charismatic capacites degenerate into those of the zealot or fanatic. –Taken from Flower Essence Repertory by P. Kaminski and R. Katz