St. John’s wort (Hypericum perforatum) is a perennial herb native to Europe, and now grows in temperate zones world-wide. It has been used therapeutically for many centuries, and its use as a medicinal herb was documented by Hippocrates in ancient Greece. Its name stems from the fact that it usually blooms around St. John’s Day, the 24th of June. The word wort simply means an herbaceous plant, and appears as part of the names of other herbs, such as mugwort and motherwort. Other common names for St. John’s wort include Chase-devil, Goat weed, Klamath weed and Tipton’s weed. St. John’s wort produces bright yellow flowers that contain a blood red juice. The medicinal properties are found in the leaves and flowers.
Therapeutic Uses of St. John’s Wort
St. John’s Wort has analgesic, antibacterial, antiviral and anti-inflammatory activity. It is useful as a pain reliever when taken internally, particularly for nerve pain such as neuralgia and sciatica, as well as conditions such as rheumatism and joint pain. Topically, it can be made into a lotion or oil infusion and used to treat sunburn and speed up the healing of minor burns, cuts, bruises or abrasions. It is also recommended to treat hemorrhoids. Its anti-viral activity makes it useful for the treatment of cold sores, which are caused by the herpes simplex virus, and other viral ailments such as shingles.
St. John’s wort has sedative and nervine properties, and can be used as a calmative for anxiety or irritability. It helps to relieve mood swings and other emotional symptoms associated with menopause and premenstrual syndrome, and it has been shown to be effective for mild to moderate depression, as well as seasonal affective disorder (SAD), a type of depression that can occur in the winter months due to lack of sunlight.
St. John’s wort contains the phytochemicals hypericin and hyperforin, which appear to bring about physiological effects similar to those produced by prescription antidepressants such as selective serotonin reuptake inhibitors (SSRI) and monoamine oxidase inhibitors (MAOI). These drugs act by preventing the neurotransmitters serotonin, dopamine and norepinephrine, which have an effect on mood, from being absorbed by nerve cells in the brain.
St. John’s wort can be taken in capsule form containing standardized extract, as a tincture, or the dried herb can be made into a tea by steeping 2 or 3 teaspoons in a cup of boiling water.
Cautions and Contraindications
St. John’s Wort can make the skin more sensitive to the sun. Those who sunburn easily should wear sunscreen and protect themselves from excessive sun exposure while taking this herb. St. John’s Wort can interfere with the effects of prescription antidepressants and other pharmaceutical drugs. This information is for educational purposes only. If you have a health concern, consult a qualified health care provider.
Duke, James A. The Green Pharmacy Herbal Handbook. St. Martin’s Press, 2000.