One of the most extensively researched herbs, St John's Wort is effective in anxiety and nervous excitement and may also improve sleep patterns due to its impact on serotonin activity in the brain. St John's Wort also displays powerful anti-viral activity as well as anti-microbial activity and may be useful in viral attacks including cold sores. Caution: Should not be taken by people taking prescription antidepressants or any medication tat interacts with MAO inhibitors.
