St. John's Wort

I still get a thrill when I discover a medicinal herb thriving in forest or field. With its cheery yellow flowers, unique blood red pigment, and equally colourful history, St. John’s wort is one of my favourite healing plants.

One of my first in-the-field experiences with St. John’s wort was during a visit to Nova Scotia. I was enjoying a summer hike with my family through a meadowed lot when we encountered a sea of brilliant yellow.

I had previously studied St. John’s wort in botany class. One little squeeze of an unopened flower bud confirmed it–I gleefully held up a crimson-stained thumb and forefinger. Yes, it was Hypericum perforatum, all right!

A Healing Tradition

It is easy to understand why the ancients considered St. John’s wort to be under the domain of the sun. The flowers tend to appear during midsummer, its petals are a golden yellow, and the stamens radiate like the sun’s rays. In medieval times the plant acquired the name Sol terrestris, meaning “terrestrial sun.” The Celts used the herb for their solstice ceremonies, when it was customary to wear a sprig of St. John’s wort to mark midsummer day.

St. John’s wort was also used in celebrations relating to St. John the Baptist, whose feast day falls on June 24, around the time the herb flowers. On a darker note, the bloody red pigment is symbolic of the blood of St. John who, according to the Canonical Gospels, was imprisoned and beheaded by Herod Antipas in about 30 AD.

Upon close inspection, the petals are edged with tiny black spots, resembling perforations, hence the botanical name Hypericum perforatum.

The Greeks and Romans used the herb for healing. In the 16th century, herbalist John Gerard recommended it as “a most precious plant for deep wounds.” One of my favourite 17th-century herbalists, Nicholas Culpeper, writes: “A singular wound herb; boiled in wine and drank, it healeth inward hurts or bruises.” In the 19th century, the North American Eclectic physicians used St. John’s wort for wound healing, menstrual cramping, and for treatment of nervous conditions.

Modern Analysis and Use

St. John’s wort is chemically complex compared to pharmaceutical drugs. Modern analysis has enabled researchers to identify the herb’s chemical characteristics. Key constituents include naphthodianthrones hypericin and pseudohypericin, flavonoids, and phenolic compounds.

In modern clinical practice, herbalists and other health care professionals recommend St. John’s wort for the treatment of mild to moderate depression, anxiety, seasonal affective disorder, neuralgia, and for viral infections that include cold sores, chicken pox, and shingles.

Doctors in Germany commonly prescribe St. John’s wort as an antidepressant, and it is reportedly prescribed four times more often than the antidepressant drug, fluoxetine hydrochloride (Prozac). Due to its increasing popularity, in 1998 the US Pharmacopoeia and National Formulary published a monograph for St. John’s wort as part of its botanical monograph series.

A Research Bonanza

St. John’s wort is one of the most widely researched herbs, with many studies supporting its traditional uses. Since 1979, more than 30 controlled trials with St. John’s wort have involved thousands of patients with depressive disorders. Most studies lasted 28 to 42 days with daily dosages of 900 mg of an extract standardized to 0.3 percent hypericin.

At least 15 controlled studies have focused on a methanolic extract of St. John’s wort and 12 controlled studies have focused on four additional preparations made from ethanolic extracts. They have confirmed the antidepressant action of the herb in humans.

Several recent trials found that the extract compared positively with selective serotonin reuptake inhibitor (SSRI) medications, especially for the treatment of patients experiencing depression and anxiety symptoms. In one of these trials, the dose of St. John’s wort was the equivalent to 4.8 g per day of dried herb.

As an herbalist I think that our medicines should be as natural, sustainable, and inexpensive as possible. It is wonderful to think that we can cultivate, harvest, and make effective medicines from the earth.

With safety in mind I would recommend that individuals interested in using St. John’s wort contact their qualified practitioner for professional advice about proper dosage and potential contraindications.