Hypericum perforatum is also known as Hardhay, Amber, Guttiferae, Goat weed, Tipton weed, Klamath weed, and St. John's wort. It's a member of the Hypericaceae family. Even though most plants in this family have little or no medicinal value, St. John's wort has been known as a medicinal herb for centuries with all parts being used. However, traditionally only the dried flowers are used in supplements.

Although native to Europe, Northern Africa and western Asia, this perennial plant was introduced in to many regions of the world and can now be found in meadows, dry pastures and alongside roadbeds virtually worldwide. Growing as high as three feet, this plant has a distinctive yellow flower with blackish looking pin-spots and yellow-green, oval shaped leaves.

St. John's wort has had a long and fabled history. Used by ancient Greeks and Romans to ward against evil spirits, sprigs of the plant were place upon the statues of their gods. During medieval times, the Europeans used the plant to treat all forms of madness and thought the plant to have many magical properties since it blooms near the Summer Solstice.

It is believed that it's blooming date is also responsible for the plant's name since the bright yellow flowers are clearly present on June 24th, the feast day for the Saint John the Baptist. Early Christians traditionally gathered the plant on the feast day. Then soaked it in olive oil until the oil turned blood red - a phenomenon caused by the hypericum - which was thought to symbolize the blood of the martyred John the Baptist. On the eve of his feast day, the plant was also brought into the houses and placed under pillows or was cast into bonfires to ward off evil spirits. Often this red oil was used to bless crops. Thus, the plant is known as St. John's wort. (Incidentally, wort is an English word for plant.)

The historical medical use of this plant is also well documented with the first written record referring to St. John's wort in the first century AD. In his famous book on natural history, Pliny the Elder refers to hypericon, noting that "The seed is of a bracing quality, checks diarrhoea and promotes urine. It is taken with wine for bladder troubles."

The next notable mention of St. John's wort was buy Dioscorides, a Roman army surgeon, recommended drinking the herb in special liquids, "For it expels cholerick excrements." in his medical text. He also recommended rubbing it on burns. Paracelsus, a medical authority of the Renaissance also wrote of using St. John's wort to treat wounds. He was also the first to mention using it for psychotic symptoms which he called "phatasmata".

Perhaps the most important writing on St. John's wort came in 1630AD when Agelo Sala stated that St. John's wort had an excellent reputation for treating illnesses of the imagination, melancholia, anxiety and disturbances of understanding. He wrote, "St. John's wort cures these disorders as quick as lightening."

However, even during these more enlightened times, medical fact and superstitious fancy were often blurred. One of the earliest compendiums of drugs, the Saltenitan drug list of the thirteenth century refers to St. John"s wort as herba demonis fuga, or the herb that chases away the devil. Another medical book published in the sixteenth century refers to the plant as Fuga demonum, or devil's scourge, a term that was repeated frequently in the literature of the next several hundred years.

The use of St. John's wort continued to spread, mostly through "wise women" and midwifes. There is even evidence that once this remarkable herb was introduced to America, the American Indians used it in the treatment of Tuberculosis and other breathing ailments.

Soldiers also knew the uses of St. John's wort. Often Crusaders and, later, Civil War soldiers would collect the plant to use on battle wounds. Many soldiers' journals record the use of a wine made with St. John's wort that would steady the nerves.

However, the story was different for "established medicine". For the three centuries after Sala's writings the use of hypericum to treat melancholia was securely incorporated in German literature but was curiously absent from British and American literature, which stressed the superficial use of the herb for the treatment of burns and wounds. Perhaps this is why the plant fell into disuse by most European cultures during the 19th century, and is only now making a strong come back. Today, St. John's wort is considered a legitimate alternative to many antidepressants. Though, in Germany, where its uses were never forgotten, it is prescribed twenty times more often then the popular pharmaceutical drugs Zoloft and Prozac.