St. John’s wort is an herb native to Europe found mainly in meadows and woodland areas and the use of St. John’s Wort dates back to the ancient Greeks and Hippocrates mentioned the use of St. John’s Wort flowers. In general St John’s Wort has been used as herbal support against depression and anxiety, but please always seek medical clarification. 

There are some countries in Europe who have disbanded the use of St. John’s Wort products, as there may be interactions with people who use St Johns Wort along with other anti-depressant prescription medicines. 
A 2009 systematic review of 29 international studies suggested that St. John’s wort may be better than a placebo (an inactive substance that appears identical to the study substance) and as effective as standard prescription antidepressants for major depression of mild to moderate severity. St. John’s wort also appeared to have fewer side effects than standard antidepressants. The studies—conducted in German-speaking countries where St. John’s wort has a long history of use by medical professionals—reported more positive results than those done in other countries, including the United States. – www. nccih.nih.gov

Caution must also be made against St John’s Wort as it may affect the effectiveness of oral birth control so again advice should be sought prior to use.