St John's Wort is one of the best researched herbal remedies. St John's Wort also known as Tipton's weed, rosin rose, goat weed, chase-devil or Klamath weed, is widely used as an herbal treatment for depression. St Johns Wort has long been used as a folk remedy for emotional disorders. It was once thought to rid the body of evil spirits. St Johns Wort has also been used for wound healing and for a variety of other conditions. A number of active ingredients are known to be present in the hypericum extract, the most important ones being hypericin, hyperforin, flavanols and xanthones. Hypericum extract is thought to work in a similar way to antidepressant medicines, by affecting levels of neurotransmitters such as serotonin in the brain (however, the exact mechanism of action is not known).