Nature's Harbor St. John's Wort is an herbal extract commonly used to treat mild depression and anxiety disorders. Clinical studies confirm that St. John's Wort enhances mood and psychological well being as effectively as commonly used anti-depressants with fewer side effects. The herbal extract has a complex composition of elements that work together to inhibit Serotonin (5-HTP) re-uptake, much like conventional anti-depressants.