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Saint John's wort

 
Medical Encyclopedia: St. John's Wort
 

Definition

Hypericum perforatum is the most medicinally important species of the Hypericum genus, commonly known as St. John's wort. There are as many as 400 species in the genus, which is part of the Guttiferae family. Native to Europe, St. John's wort is found throughout the world. It thrives in sunny fields, open woods, and gravelly roadsides. Early colonists brought this valuable medicinal to North America, and the plant has become naturalized in the eastern United States and California, as well as in Australia, New Zealand, eastern Asia, and South America.

The entire plant, particularly the round, black seed, exudes a slight, turpentine-like odor. The woody, branched root spreads from the base with runners that produce numerous stalks. The simple, dark green leaves are veined and grow in opposite, oblong-obvate pairs on round, branching stalks that reach 3 ft (91.4 cm) high. Tiny holes, visible when the leaf is held to the light, are actually transparent oil glands containing the chemical photo sensitizer known as hypericin. These characteristic holes inspired the species name, perforatum, Latin for perforated. The bright yellow, star-shaped flowers, often clustered in a trio, have five petals. Each blossom has many showy stamens. Black dots along the margins of the blossom contain more of the red-pigmented chemical hypericin. The herb is also useful as a dye. The flowers bloom in branching, flat-topped clusters atop the stalks in mid-summer, around the time of the summer solstice. St. John's wort, sometimes called devil's flight or grace of God, was believed to have magical properties to ward off evil spirits. It's generic name hypericum is derived from a Greek word meaning "over an apparition." The herb was traditionally gathered on mid-summer's eve, June 23. This date was later christianized as the eve of the feast day of St. John the Baptist. This folk custom gave the plant its popular name. The Anglo-Saxon word wort means medicinal herb.

— Clare Hanrahan



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Dictionary: Saint John's wort  Saint John's·wort (jŏnz'wûrt', -wôrt') pronunciation
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also n.

Any of various herbs or shrubs of the genus Hypericum, having yellow flowers with five petals and numerous stamens that are united at the base into three to five fascicles.

[From its being gathered on Saint John's Eve to ward off evil.]


 
Drug Info: St. John's Wort, Hypericum perforatum
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Brand names: Centrum® Herbals St. Johns Wort, Herbal Plus® Fingerprinted™ St. John's Wort, Kira™, Movana™, Oleomed™ Mood, Quanterra™ Emotional Balance

Chemical formula:



St. John's Wort, Hypericum perforatum oral dosage forms

What is St. John's wort?

St. John's wort (Centrum® Herbals St. John's Wort, Hypericalm™, Kira®, Movana™, Quanterra™ Emotional Balance) is an herb or dietary supplement that is being promoted for its ability to improve mildly depressed moods. The herb does not appear to be very effective for persons with severe depression. Its yellow flowers are especially bright on June 24, the traditional birthday of St. John the Baptist, hence the name 'St. John's wort'. Other names include 'goat weed' or 'klamath weed'. This herb is not FDA approved at this time. Many different products containing St. John's wort in combination with other herbs are available.

What should I tell my health care provider before I take this medicine?

It is important for you to tell your prescriber or health care professional or other health care professional that you are using St. John's wort. Some herbs exert potent effects and may interact with other drugs you are taking.

You should discuss St. John's wort with your health care professional BEFORE taking it if you have any of these conditions:
• heart disease or high blood pressure
• heart, liver, kidney or other organ transplant
• history of emotional illness, such as anxiety, mania, or depression
• infection with the human immunodeficiency virus (HIV or AIDS)
• kidney disease
• liver disease
• stroke
• thoughts of suicide
• an unusual or allergic reaction to St. John's wort, other medicines, foods, dyes, or preservatives
• pregnant or trying to get pregnant
• breast-feeding

How should I use this medicine?

This herb should be taken orally (i.e., swallowed). Follow the directions on the package labeling, or talk to your health care professional for advice. The effects of St. John's wort take several weeks to appear so it should be taken as directed for several weeks for best results.

Contact your pediatrician or health care professional regarding the use of this herb in children. Special care may be needed.

What drug(s) may interact with St. John's wort?

St. John's wort may interact with many prescription and non-prescription medications. Some of these interactions may be very important, including some that could reduce the effectiveness of your prescribed medications. You should check with your health care professional prior to taking St. John's wort if you are taking other medications. Some of the important interactions are listed:

amiodarone
• birth control pills, injections, implants, or other female hormones
bosentan
caffeine
carbamazepine
• cough syrups
cyclosporine
digoxin
• doxcercalciferol
• excessive intake of tyramine-containing foods (see below)
fexofenadine
• medications for high blood pressure or heart-related health problems
• medications for depression, anxiety, difficulty sleeping, or other emotional or psychiatric problems
• medications for the treatment of cancer (chemotherapy)
• medications for the treatment of HIV infection
paricalcitol
• red yeast rice
sirolimus
• some medicines for high cholesterol (atorvastatin, lovastatin, simvastatin)
• some medications for pain
tacrolimus
temsirolimus
• theophylline
warfarin

For many herbs, interactions with other medications are unknown. That is why you should always be careful when mixing herbal remedies with traditional medications. If you take any other medications, consult with your health care professional prior to taking St. John's wort.

Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines, nutritional supplements, or herbal products. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.

What should I watch for while taking St. John's wort?

Since St. John's wort is derived from a plant, allergic reactions are possible. Stop using this herb if you develop a rash.

Do not use St. John's wort if you are currently being treated for a mental or emotional problem such as depression or anxiety, except on the advice of your health care professional. St. John's wort may interfere with your treatments. Also do not stop your prescribed treatments without talking to your prescriber or health care professional. If you are treating yourself with St. John's wort, seek medical advice if your mood does not improve in 6—8 weeks or if you have suicidal thoughts.

You should check your blood pressure closely while taking St. John's wort if you have high blood pressure.

Until more is known about the actions of this herb, it may be advisable to limit intake of certain foods and beverages that contain tyramine. Foods that contain tyramine might produce severe headaches, a rise in blood pressure, or irregular heart beat if taken in excess with St. John's wort. Fortunately these problems have not been noted to occur frequently with St. John's wort. Examples of foods that contain significant amounts of tyramine include aged cheeses; aged, smoked, pickled, or processed meats or fish (such as bologna, pepperoni, salami, herring); beers and ales; red wines; sherry; liqueurs; figs; raisins; soy sauce; yeast/protein extracts; bean curd; fava bean pods; or any over-ripe fruit. Ask your prescriber or health care professional, pharmacist, or nutritionist for a complete listing of tyramine-containing foods and whether you should avoid them. Also, limit drinks containing caffeine, such as tea, coffee, chocolate, or cola.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water will help.

St. John's wort can increase your sensitivity to the sun and you may burn more easily, or develop stinging pain in sun-exposed areas. Always use sunscreen and protective clothing during long periods outdoors. Do not use tanning booths or sun lamps while on this herb.

Different brands of St. John's wort might contain different amounts of active ingredient so be careful to use the same brand. A standardized product is more likely to contain the same amount of herb from dose to dose. Your health care professional or pharmacist can assist you in finding a standardized product.

Inform your prescriber you are taking this herb prior to scheduling surgery. St. John's wort might interact with medications given during surgery or anesthesia. Usually the herb should be discontinued at least 2 to 3 weeks prior to any surgery. Consult your health care professional for advice.

What side effects may I notice from using St. John's wort?

Side effects that you should report to your prescriber or health care professional as soon as possible:
• confusion, forgetfulness
• difficulty staying awake or alert
• anxiety, nervousness, racing thoughts, or other mood changes
• rapid heartbeat or "palpitations"
• rash
• shortness of breath or difficulty breathing
• sunburns after being in sunlight or ultraviolet light, or "stinging pains" of sun-exposed areas

Minor side effects (report to your prescriber or health care professional if they continue or are bothersome):
Rare or less common:
• sexual difficulties
• difficulty sleeping or restlessness
More common:
• upset stomach
• drowsiness
• dry mouth

Where can I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 8 and 25 degrees C (46 and 77 degrees F); do not freeze. Throw away any unused herb after the expiration date.

GENERAL INFORMATION REGARDING DIETARY SUPPLEMENTS:
Dietary supplements include amino acids, vitamins, minerals, herbs, botanicals, and other plant-derived substances, and extracts of these substances. These products are easy to identify as they must state "Dietary Supplement" on the label. A "Supplement Facts" panel is provided on the label for most products. Supplements are not drugs and are not regulated like drugs. You should note that rigid quality control standards are not required for dietary supplements. Big differences in potency and purity of these products can occur. Scientific data to support the use of a dietary supplement for a certain disease or ailment may not be available. This product is not intended to diagnose, treat, cure or prevent any disease.

The Food and Drug Administration suggests the following to help consumers protect themselves:
• Always read product labels and follow directions.
• "Natural" doesn't mean a product is safe for humans to take.
• Look for products containing ingredients with the "USP" notation. This indicates the manufacturer followed the standards of the US Pharmacopoeia.
• Supplements produced or distributed by a nationally known food or drug company are more likely to be made under tight controls as these companies have standards in place for their other products. You can write to the company for more information about how the product was made.

Last updated: 7/1/2002

Important Disclaimer: The drug information provided here is for educational purposes only. It is intended to supplement, not substitute for, the diagnosis, treatment and advice of a medical professional. This drug information does not cover all possible uses, precautions, side effects and interactions. It should not be construed to indicate that this or any drug is safe for you. Consult your medical professional for guidance before using any prescription or over the counter drugs.

 

Description

Hypericum perforatum is the most medicinally important species of the Hypericum genus, commonly known as St. John's wort or Klamath weed. There are as many as 400 species in the genus, which belongs to the Clusiaceae family. Native to Europe, St. John's wort is found throughout the world. It thrives in sunny fields, open woods, and gravelly roadsides. Early colonists brought this plant to North America, and it has become naturalized in the eastern United States and California, as well as in Australia, New Zealand, eastern Asia, and South America. As of 2004, St. John's wort is one of the most commonly used herbs in the United States, especially among women.

The entire plant, particularly its round black seeds, exudes a slight turpentine-like odor. The woody-branched root spreads from the base with runners that produce numerous stalks. The simple dark green leaves are veined and grow in opposite, oblong, or oval pairs on round branching stalks that reach as high as 3 ft (91.4 cm). Tiny holes, visible when the leaf is held to the light, are actually transparent oil glands containing a chemical known as hypericin. These characteristic holes inspired the species name, Perforatum, which is the Latin word for "perforated." The bright yellow star-shaped flowers, often clustered in groups of three, have five petals. Black dots along the margins of the blossom contain more hypericin. The flowers bloom in branching flat-topped clusters atop the stalks, around the time of the summer solstice. St. John's wort, sometimes called devil's flight or grace of God, was believed to contain magical properties that ward off evil spirits. Its generic name, Hypericum, is derived from a Greek word meaning "over an apparition." The herb was traditionally gathered on midsummer's eve, June 23. This date was later celebrated in the Christian Church as the eve of the feast day of St. John the Baptist. This folk custom gave the plant its popular name. The Anglo-Saxon word "wort" means "medicinal herb."

General Use

St. John's wort has been known for its medicinal properties as far back as Roman times. On the battlefield, it was a valued remedy that promoted healing from trauma and inflammation. The herb is regarded as a vulnerary, and can speed the healing of wounds, bruises, ulcers, and burns. It is also popularly used as a nervine for its calming effect, easing tension and anxiety, relieving mild depression, and soothing women's mood swings during menopause. The bittersweet herb is licensed in Germany for use in mild depression, anxiety, and sleeplessness. It is said to be helpful in nerve injury and trauma, and was used in the past to speed healing after brain surgery. Its antispasmodic properties have been thought to ease uterine cramping and menstrual difficulties. St. John's wort may also be used as an expectorant.

The hypericin in St. John's wort possesses antiviral properties that are said to be effective against certain cancers. An infusion of the plant taken as a tea has been helpful in treating bedwetting in children. The oil has been used internally to treat colic, intestinal worms, and abdominal pain. The plant's medicinal parts are its fresh leaves and flowers. This herbal remedy has been extensively tested in West Germany, and is dispensed throughout Germany as a popular medicine called Johanniskraut. Commercially prepared extracts are commonly standardized to contain 0.3% hypericin.

Clinical Studies

In contrast to early European reports made in the 1980s, more recent clinical studies tend to undermine the claims made for St. John's wort as a possible treatment for HIV infection and depression. As of 2002, health care professionals and regulatory agencies in Europe were advised to warn AIDS patients that St. John's wort decreases the effectiveness of drugs known as HIV protease inhibitors. In addition, the National Center for Complementary and Alternative Medicine (NCCAM) in the United States released the results of a large-scale multi-site study in April 2002, which reported that St. John's wort is no more effective than a placebo for treating major depression of moderate severity. The study was also published in the Journal of the American Medical Association. Additional studies being conducted in several countries are researching the interactions between St. John's wort and various types of prescription medications.

Preparations

An oil extract can be purchased commercially or prepared by combining fresh St. John's wort flowers and leaves in a glass jar with sunflower or olive oil. The container should be sealed with an airtight lid, and placed on a sunny windowsill for four to six weeks. It should be shaken daily. When the oil absorbs the red pigment, the mixture is strained through muslin or cheesecloth, and stored in a dark container. The medicinal oil maintains its potency for two years or more. The oil of St. John's wort has been known in folk culture as "Oil of Jesus." This oil forms a rub used for painful joints, varicose veins, muscle strain, arthritis, and rheumatism. Placed in a compress, it can help to heal wounds and inflammation, and relieve the pain of deep bruising.

An infusion is made by pouring one pint of boiling water over 1 oz (28 g) of dried herb, or 2 oz (57 g) of fresh, minced flower and leaf. It is steeped in a glass or enamel pot for five to 10 minutes, then strained and covered. The tea should be consumed while it is warm. A general dose is one cup, up to three times daily.

To prepare a capsule, the leaves and flowers are dried, and ground with a mortar and pestle into a fine powder. The mixture is then placed in gelatin capsules. The potency of the herb varies with the soil, climate, and harvesting conditions of the plant. A standardized extract of 0.3% hypericin extract, commercially prepared from a reputable source, is more likely to yield reliable results. Standard dosage is up to three 300 mg capsules of 0.3% standardized extract daily.

A tincture is prepared by combining one part fresh herb to three parts alcohol (50% alcohol/water solution) in a glass container. The mixture is placed in a dark place, and shaken daily for two weeks. Then it is strained through muslin or cheesecloth, and stored in a dark bottle. The tincture should maintain potency for two years. Standard dosage, unless otherwise prescribed, is 0.24–1 tsp added to 8 oz (227 g) of water, up to three times daily.

A salve can be made by warming 2 oz (57 g) of prepared oil extract in a double boiler. Once warmed, 1 oz (28 g) of grated beeswax is added and mixed until melted. The mixture is poured into a glass jar and allowed to cool. The salve can be stored for up to one year. The remedy keeps best if refrigerated after preparation. The salve is useful in treating burns, wounds, and soothing painful muscles. It is also a good skin softener. St. John's wort salve may be prepared in combination with calendula extract (Calendula officinalis) for application on bruises.

Precautions

There are a number of important precautions to observe in using St. John's wort. Pregnant or lactating women should not use the herb at all. Persons taking prescription antidepressants of any kind should not use St. John's wort at the same time, as the herb may precipitate a health crisis known as serotonin syndrome. Serotonin syndrome is potentially life-threatening, and is characterized by changes in level of consciousness, behavior, and neuromotor functioning as a result of increased levels of the neurotransmitter serotonin in the central nervous system. Drug interactions are the most common cause of serotonin syndrome. Several cases of serotonin syndrome have been reported in patients who were taking St. John's wort by itself or in combination with SSRIs, fenfluramine (Pondimin), or nefazodone (Serzone). Persons using the herb should discontinue it a minimum of two weeks prior to any surgery requiring general anesthesia, as it interacts with a number of intravenous and inhaled anesthetics.

It is also important for persons using St. John's wort to purchase the herb from a reputable source, as the quality of herbal products sold in the United States and Canada varies widely. One study of 10 popular herb samples, including St. John's wort, reported in 2003 that each herb had "a large range in label ingredients and recommended daily dose (RDD) across available products." The researchers recommended that physicians and consumers pay very close attention to labels on over the counter (OTC) herbal products.

In addition to the herb's potential risks to humans, it can be toxic to livestock. Toxic effects in cattle include reports of edema of the ears, eyelids, and the face due to photosensitization after the animal eats the herb. Exposure to sunlight activates the hypericin in the plant. Adverse effects have been reported in horses, sheep, and swine, including a staggering gait and blistering or peeling of the skin. Smaller animals, such as rabbits, suffer severe side effects from accidental ingestion of St. John's wort. The Veterinary Botanical Medicine Association (VBMA), which was founded in 2002 as an offshoot of the American Veterinary Medical Association (AVMA), offers a page on its website for reporting adverse effects of St. John's wort or any other herb in cats, dogs, or other animals.

Side Effects

When used either internally or externally, the herb may cause photodermatitis in humans with fair or sensitive skin, following exposure to sunlight or other sources of ultraviolet light. There have also been some case reports of side effects in breast-feeding women taking hypericum extract. Changes in the nutritional quality and flavor of the milk, as well as reduction or cessation of lactation, have been reported. In addition, St. John's wort has been known to cause headaches, stiff neck, nausea or vomiting, and high blood pressure in susceptible individuals.

Interactions

St. John's wort has a number of problematic interactions with many drugs. It has been reported to interact with amphetamines, asthma inhalants, decongestants, diet pills, narcotics, tryptophan and tyrosine (amino acids), as well as antidepressant medications and certain foods. It has also been reported to interfere with the effectiveness of birth control pills as well as with indinavir (Crixivan) and other AIDS medications. Moreover, anesthesiologists have reported that the herb increases bleeding time in patients under general anesthesia. Patients should always consult a mainstream health practitioner before using St. John's wort, and should discontinue taking it at least two weeks prior to major surgery.

Resources

Books

Blumenthal, Mark. The Complete German Commission E Monographs, Therapeutic Guide to Herbal Medicines. American Botanical Council, Boston: Integrative Medicine Communications, 1998.

Bown, Deni. The Herb Society of America, Encyclopedia of Herbs & Their Uses. New York: DK Publishing, Inc., 1995.

Foster, Steven, and James A. Duke. A Field Guide to Medicinal Plants. New York: Peterson Field Guides, Houghton Mifflin Company, 1990.

Hoffmann, David. The New Holistic Herbal. Massachusetts: Element Books, 1992.

McIntyre, Anne. The Medicinal Garden. New York: Henry Holt and Company Inc., 1997.

Periodicals

Deshmukh, R., and K. Franco. "Talking to Patients About St. John's Wort." Cleveland Clinic Journal of Medicine 70 (November 2003): 990.

Finfgeld, D. L. "Serotonin Syndrome and the Use of SSRIs." Journal of Psychosocial Nursing and Mental Health Services 42 (February 2004): 16–20.

Garrard, J., S. Harms, L. E. Eberly, and A. Matiak. "Variations in Product Choices of Frequently Purchased Herbs: Caveat Emptor." Archives of Internal Medicine 163 (October 27, 2003): 2290–95.

Henderson, L., Q. Y. Yue, C. Bergquist, et al. "St. John's Wort (Hypericum perforatum): Drug Interactions and Clinical Outcomes." British Journal of Clinical Pharmacology 54 (October 2002): 349–56.

Hodges, P. J., and P. C. Kam. "The Peri-Operative Implications of Herbal Medicines." Anaesthesia 57 (September 2002): 889–99.

Hypericum Depression Trial Study Group. "Effect of Hypericum perforatum (St. John's Wort) in Major Depressive Disorder: A Randomized, Controlled Trial." Journal of the American Medical Association (JAMA) 287 (April 10, 2002): 1807–14.

Pfrunder, A., M. Schiesser, S. Gerber, et al. "Interaction of St. John's Wort with Low-Dose Oral Contraceptive Therapy: A Randomized Controlled Trial." British Journal of Clinical Pharmacology 56 (December 2003): 683–90.

Steinbach, Harvey, M.D. "Serotonin Syndrome: How to Avoid, Identify, and Treat Dangerous Drug Interactions." CurrentPsychiatry Online 2 (May 2003). .

Yu, S. M., R. M. Ghandour, and Z. J. Huang. "Herbal Supplement Use Among US Women, 2000." Journal of the American Medical Women's Association 59 (Winter 2004): 17–24.

Organizations

American Botanical Council. P.O. Box 201660, Austin, TX 78720-1660.

Food and Drug Administration (FDA). 5600 Fishers Lane, Rockville, MD 20857. (888) 463-6332. .

Herb Research Foundation. 1007 Pearl St., Suite 200, Boulder, CO 80302. (303) 449-2265. .

National Center for Complementary and Alternative Medicine (NCCAM) Clearinghouse. P. O. Box 7923, Gaithersburg, MD 20898-7923. (888) 644-6226. Fax: (866) 464-3615. .

Veterinary Botanical Medicine Association (VBMA). c/o Susan G. Wynn, DVM, 334 Knollwood lane, Woodstock, GA 30188. E-mail: s.wynn@vbma.org. .

Other

National Center for Complementary and Alternative Medicine (NCCAM) Fact Sheet. St. John's Wort and the Treatment of Depression. Bethesda, MD: NCCAM, 2002. .

National Center for Complementary and Alternative Medicine (NCCAM) press release, 9 April 2002. "Study Shows St. John's Wort Ineffective for Major Depression of Moderate Severity." .

[Article by: Clare Hanrahan; Rebecca J. Frey, PhD]

 
Britannica Concise Encyclopedia: Saint-John's-wort
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Common name for plants in the family Hypericaceae, which contains 560 species of herbs or low shrubs in eight genera. The family is sometimes considered part of the family Guttiferae. The majority of species (about 370) belong to the genus Hypericum. Their leaves are opposite or whorled, dotted with glands, and usually have smooth margins. Several species are cultivated in temperate regions for their handsome flowers. H. perforatum, a showy golden flower grown in both the Old and New Worlds whose buds contain a red oil, has long been credited with magical and medicinal powers; today it is being widely used and studied for its possible efficacy against depression.

For more information on Saint-John's-wort, visit Britannica.com.

 
Columbia Encyclopedia: St.-John's-wort
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St.-John's-wort, any species of the large and widespread herbaceous or shrubby genus Hypericum of the family Hypericaceae (St.-John's-wort family), usually found in moist, open places and often having bright yellow flowers and dotted leaves. A St.-John's-wort is said to have been associated with the sun god Balder, because of its golden flowers, and when Balder's Day became St. John's Day the plant was likewise transferred to St. John. It was supposed to ward off evil spirits and thunderbolts, for which it was worn on St. John's Eve. Long considered to have curative powers, St.-John's-wort was traditionally used for treating wounds and has lately become popular as an herbal remedy in the treatment of mild depression; it is prepared from the dried flowering plant tops of H. perforatum, a European species. Of the North American species a few are cultivated and some are noxious weeds, poisonous to livestock. Several naturalized American plants are Asian species that were introduced by way of Europe. A species of Hypericum is one of several plants called Aaron's-beard, in this case because of the beardlike aspect of its many stamens. See rose of Sharon. St.-John's-wort is classified in the division Magnoliophyta, class Magnoliopsida, order Theales, family Hypericaceae.


 

General term for the plant species Hypericum. In classical mythology, the summer solstice was a day dedicated to the sun, and was believed to be a day on which witches held their festivities. St. John's Wort was its symbolic plant. People used to judge from it whether their future would be lucky or unlucky, as it grew they read in its progressive character their future lot. This traditional lore carried over into the Christianera, when this festival period was dedicated to St. John's Wort or root. It became a talisman against evil.

In one of the old Scottish romantic ballads, a young lady falls in love with a demon, who tells her:

Gin you wish to be leman mine [my lover]
Lay aside the St. John's Wort and the vervain.

When hung up on St. John's Day, together with a cross over the door, this plant was supposed to keep out the devil and other evil spirits. To gather the root at sunrise on St. John's Day and to retain it in the house, gave luck to the family in their undertakings, especially in those begun on that day.

 
Veterinary Dictionary: St. John's wort
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hypericum aethiopicum, H. perforatum.

 
Wikipedia: St John's wort
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St John's wort

Scientific classification
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Malpighiales
Family: Clusiaceae
Genus: Hypericum
Species: H. perforatum
Binomial name
Hypericum perforatum
L.

St John's wort (pronounced /seɪntˈdʒɒnzwərt/, or spelling pronunciations in /-wɔrt/)[1] is the plant species Hypericum perforatum, also known as Tipton's Weed or Klamath weed, but, with qualifiers, is used to refer to any species of the genus Hypericum. Therefore, H. perforatum is sometimes called Common St John's wort to differentiate it. The species of Hypericum have been placed by some in the family Hypericaceae, but more recently have been included in the Clusiaceae.[2] Approximately 370 species of the genus Hypericum exist worldwide with a native geographical distribution including temperate and subtropical regions of North America, Europe, Asia Minor, Russia, India, and China. St. John's wort is today most widely known as an herbal treatment for depression. According to the Cochrane Review, a key resource in evidence-based medicine, "the available evidence suggests that the hypericum extracts tested in the included trials are superior to placebo in patients with major depression; are similarly effective as standard antidepressants; and have fewer side effects than standard antidepressants."[3]

Contents

The plant

Hypericum perforatum is a yellow-flowering, stoloniferous or sarmentose, perennial herb indigenous to Europe, which has been introduced to many temperate areas of the world and grows wild in many meadows. The common name comes from its traditional flowering and harvesting on St John's day, 24 June. The genus name Hypericum is derived from the Greek words hyper (above) and eikon (picture), in reference to the traditional use of the plant to ward off evil, by hanging plants over a religious icon in the house during St John's day. The species name perforatum refers to the presence of small oil glands in the leaves that look like windows, which can be seen when they are held against the light.

Although Hypericum perforatum is grown commercially in some regions of south east Europe, it is listed as a noxious weed in more than twenty countries and has introduced populations in South America, India, New Zealand, Australia, and South Africa.[4] In pastures, St John’s wort acts as both a toxic and invasive weed.[5] It replaces useful vegetation to the extent of making productive land unviable or acts as an alien species in natural ecosystems. Ingestion by livestock can cause photosensitization, central nervous system depression, spontaneous abortion, and can lead to death. Effective herbicides for control of Hypericum include 2,4-D, picloram, and glyphosate. In western North America three beetles Chrysolina quadrigemina, Chrysolina hyperici and Agrilus hyperici have been introduced as biocontrol agents.

Identification

St John’s wort can be visually recognized by leaf and flower type. Yellow, five petaled flowers approximately 20 mm across occur between late Spring and early to mid Summer. Leaves exhibit obvious translucent dots when held up to the light, giving them a ‘perforated’ appearance, hence the plant's Latin name. When flowers or seed pods are crushed, a reddish/purple liquid is produced.

The translucent dots on the St John's wort leaves

Botanical description

St John's wort is a perennial plant with extensive, creeping rhizomes. Its stems are erect, branched in the upper section, and can grow to 1 m high. It has opposing, stalkless, narrow, oblong leaves which are 12 mm long or slightly larger. The leaves are yellow-green in color, with transparent dots throughout the tissue and occasionally with a few black dots on the lower surface. Its flowers measure up to 2.5 cm across, have five petals, and are colored bright yellow with conspicuous black dots. The flowers appear in broad cymes at the ends of the upper branches. The sepals are pointed, with glandular dots in the tissue. There are many stamens, which are united at the base into three bundles.

Ecology

St John’s wort has a complex life cycle that includes a mature plant cycle with vegetative and sexual reproduction. It thrives in areas with either a winter- or summer-dominant rainfall pattern; however, distribution is restricted by temperatures too low for seed germination or seedling survival. Altitudes greater than 1500 m, rainfall less than 500 mm, and a daily mean January temperature greater than 24 degrees are considered limiting thresholds. Depending on environmental and climatic conditions, and rosette age, St John’s wort will alter growth form and habit to promote survival. Summer rains are particularly effective in allowing the plant to grow vegetatively, following defoliation by insects or grazing.

The seeds can persist for decades in the soil seed bank, germinating following disturbance.[4]

Medicinal use

St John's wort is today most widely known as a herbal treatment for depression. In some countries, such as Germany, it is commonly prescribed for mild depression, especially in children, adolescents, and where cost is a concern.[6] Standardized extracts are generally available over the counter — however, in some countries (such as Ireland) a prescription is required. Extracts are usually in tablet or capsule form, and also in teabags and tinctures.

Earaches, ear infections, tinnitus

St. John's wort is also used in its extract form in ear oils/drops for ear infections, ear pain, or tinnitus. The dosage of this is likely lower than those used for depression but is still unknown.

Major depressive disorder

Seedlings of St John's wort

An analysis of 29 clinical trials with more than 5000 patients was conducted by Cochrane Collaboration. The review concluded that extracts of St. John's wort were superior to placebo in patients with major depression. St. John's wort had similar efficacy to standard antidepressants. The rate of side effects was twice lower than for newer SSRI antidepressants and five times lower than for older tricyclic antidepressants.[3]

National Center for Complementary and Alternative Medicine (NCCAM), a U.S Government Agency and other NIH-affiliated organizations hold that St John's wort has minimal or no effects beyond placebo in the treatment of major depression[7][8] This conclusion is based primarily on one trial with negative outcome conducted by NCCAM.[9] The authors of the study themselves, as well as several others pointed out the low assay sensitivity of this study, and how only limited conclusions can be drawn from its results.[10][11]

St. John's wort was not effective for patients suffering from dysthymia, a less severe and more chronic variety of depression.[12]

Other medical uses

A constituent chemical, hyperforin may be useful for treatment of alcoholism, although dosage, safety and efficacy have not been studied.[13] Hyperforin has also been found to have antibacterial properties against gram-negative bacteria, although dosage, safety and efficacy has not been studied.[14]

Hyperforin has been shown to inhibit the reuptake of the neurotransmitter norepinephrine, leading to speculation that it might alleviate the symptoms of attention-deficit hyperactivity disorder (ADHD). A randomized controlled trial of St. John's wort found no significant difference between it and placebo in the management of ADHD symptoms over eight weeks. However, the St. John's Wort extract used in the study, originally confirmed to contain 0.3% hypericin, was allowed to degrade to levels of 0.13% hypericin and 0.14% hyperforin. Given that the level of hyperforin was not ascertained at the beginning of the study, and levels of both hyperforin and hypericin were well below that used in other studies, little can be determined based on this study alone.[15]

Adverse effects and drug interactions

St John's wort is generally well tolerated, with an adverse effect profile similar to placebo.[16] The most common adverse effects reported are gastrointestinal symptoms, dizziness, confusion, tiredness and sedation.[17]

St John's wort may rarely cause photosensitivity. This can lead to visual sensitivity to light and to sunburns in situations that would not normally cause them.[16] Related to this, recent studies concluded that the extract reacts with light, both visible and ultraviolet, to produce free radicals, molecules that can damage the cells of the body. These can react with vital proteins in the eye which, if damaged, precipitate out causing cataracts.[18]

Pharmacokinetic interactions

St John's wort has been shown to cause multiple drug interactions mainly through induction of the cytochrome P450 enzyme CYP3A4, but also CYP2C9. This results in the increased metabolism of those drugs, resulting in decreased concentration and clinical effect. The principal constituent thought to be responsible is hyperforin.

Examples of drugs causing clinically-significant interactions with St John's wort
Class Drugs
antiretrovirals non-nucleoside reverse transcriptase inhibitors, protease inhibitors
benzodiazepines alprazolam, midazolam
hormonal contraception combined oral contraceptives
immunosuppressants calcineurin inhibitors, cyclosporin, tacrolimus
others digoxin, methadone, omeprazole, phenobarbitol, theophylline, warfarin, levodopa, suboxone, Irinotecan
Reference: Rossi, 2005

For a complete list, see CYP3A4 ligands and CYP2C9 ligands. For further updating on interactions and appropriate management, see Herbological.com - St John's Wort Interactions table.

Pharmacodynamic interactions

St John's wort may also contribute to serotonin syndrome in combination with other drugs which may elevate 5-HT (serotonin) levels in the central nervous system (CNS).[19]

Drugs which may contribute to serotonin syndrome with St John's wort
Class Drugs
Antidepressants MAOIs, TCAs, SSRIs, mirtazapine, venlafaxine
Opioids tramadol, pethidine
CNS stimulants phentermine, diethylpropion, amphetamines, sibutramine, cocaine
5-HT1 agonists triptans
Psychedelic drugs methylenedioxymethamphetamine (MDMA), lysergic acid diethylamide (LSD)
Others selegiline, tryptophan, buspirone, lithium, linezolid, dextromethorphan, 5-HTP
Reference: Rossi, 2005

Chemical composition

Herb and flowers contain different flavonoids (rutin, hyperoside, isoquercetin, quercitrin, quercetin, I3,II8-biapigenin, amentoflavone, astilbin, miquelianin), phenolic acids (chlorogenic acid, 3-O-coumaroylquinic acid), different naphtodianthrones (hypericin, pseudohypericin, protohypericin, protopseudohypericin), phloroglucinols (hyperforin, adhyperforin), and also essential oils (composed mainly of sesquiterpenes). The naphthodianthrones hypericin and pseudohypericin along with the phloroglucinol derivative hyperforin are thought to be the active components.

[20][21][22].

Pharmacology

The exact mechanism by which St John's wort — and even conventional antidepressants — functions is unclear and subject to conjecture. The St John's wort mechanism is believed to involve inhibition of serotonin (5-HT) reuptake, much like the conventional selective serotonin reuptake inhibitor (SSRI) antidepressants.[23] The major active antidepressive constituents in St John's wort are thought to be hyperforin and hypericin, although other biologically active constituents present, for example, flavonoids and tannins, may also be involved.[24][25][26]

Some believe that hyperforin is the major constituent responsible for antidepressant activity, and it has been shown to inhibit the uptake of 5-HT, dopamine, noradrenaline, GABA and glutamate. [25] On the other hand, a hyperforin free extract of St John's wort (Ze 117 - Remotiv) has been shown to still have significant antidepressive effects.[27][28]

Hypericum poisoning (livestock)

Clinical signs

In large doses, St John's wort is poisonous to grazing livestock (cattle, sheep, goats, horses).[5]

St John's Wort, New England (Australia)

Behavioural signs of poisoning are general restlessness and skin irritation. Restlessness is often indicated by pawing of the ground, head shaking, head rubbing, and occasional hindlimb weakness with knuckling over, panting, confusion and depression. Mania and hyperactivity may also result including running in circles until exhausted. Observations of thick wort infestations by Australian graziers include the appearance of circular patches giving hillsides a ‘crop circle’ appearance, possibly from this phenomenon. Animals typically seek shade and have reduced appetite. Hypersensitivity to water has been noted, and convulsions may occur following a knock to the head. Although general aversion to water is noted, some may seek water for relief.

Severe skin irritation is physically apparent, with reddening of non-pigmented and unprotected areas. This subsequently leads to itch and rubbing, followed by further inflammation, exudation and scab formation. Lesions and inflammation that occur are said to resemble the conditions seen in foot and mouth disease. Sheep have been observed to have face swelling, dermatitis, and wool falling off due to rubbing. Lactating animals may cease or have reduced milk production, pregnant animals may abort. Lesions on udders are often apparent. Horses may show signs of anorexia, depression (with a comatose state), dilated pupils, and injected conjunctiva.

Early diagnosis

Increased respiration and heart rate is typically observed while one of the early signs of St John’s wort poisoning is an abnormal increase in body temperature. Affected animals will lose weight, or fail to gain weight; young animals more affected than old animals. In severe cases death may occur, as a direct result of starvation, or because of secondary disease or septicaemia of lesions. Some affected animals may accidentally drown. Poor performance of suckling lambs (pigmented and non-pigmented) has been noted, suggesting a reduction in the milk production, or the transmission of a toxin in the milk.

Photosensitisation

Most clinical signs are caused by photosensitisation.[29] Plants may induce either primary or secondary photosensitisation: primary photosensitisation directly from chemicals contained in ingested plants, or secondary photosensitisation from plant-associated damage to the liver. Araya and Ford (1981) explored changes in liver function and concluded there was no evidence of Hypericum-related effect on the excretory capacity of the liver, or any interference was minimal and temporary. However, at high and continuous dose rates changes in blood plasma indicative of some liver damage have been observed.

Photosensitisation causes skin inflammation by a mechanism involving a pigment or photodynamic compound, which when activated by a certain wavelength of light leads to oxidation reactions in vivo. This leads to lesions of tissue, particularly noticeable on and around parts of skin exposed to light. Lightly covered or poorly pigmented areas are most conspicuous. Removal of affected animals from sunlight results in reduced symptoms of poisoning.

History

The first recorded use of Hypericum for medicinal purposes dates back to ancient Greece, and it has been used ever since. Hypericum was also used by Native Americans internally as an abortifacient and externally as an anti-inflammatory, astringent, and antiseptic.

Its use as a herbal tea has long been enjoyed.

The flowers and stems of St John's wort have also been used to produce red and yellow dyes.

References

  1. ^ Random House
  2. ^ "#914: Hypericum frondosum - Floridata.com". http://www.floridata.com/ref/H/hype_fro.cfm. Retrieved on 2008-11-02. 
  3. ^ a b Linde K, Berner MM, Kriston L (2008). "St John's wort for major depression". Cochrane Database Syst Rev 8 (4): CD000448. doi:10.1002/14651858.CD000448.pub3. PMID 18843608. 
  4. ^ a b "SPECIES: Hypericum perforatum". Fire Effects Information System. http://www.invasive.org/weedcd/pdfs/feis/Hypericumperforatum.pdf. 
  5. ^ a b St John's wort
  6. ^ Fegert JM, Kölch M, Zito JM, Glaeske G, Janhsen K (2006). "Antidepressant use in children and adolescents in Germany". J Child Adolesc Psychopharmacol 16 (1-2): 197–206. doi:10.1089/cap.2006.16.197. PMID 16553540. 
  7. ^ St. John's Wort and Depression NCCAM on St John's wort and depression]
  8. ^ How is depression detected and treated? NIMH on depression, including a section on St John's wort
  9. ^ Hypericum Depression Trial Study Group (2002). "Effect of Hypericum perforatum (St John's wort) in major depressive disorder: a randomized controlled trial". JAMA 287 (14): 1807–14. doi:10.1001/jama.287.14.1807. PMID 11939866. 
  10. ^ Kupfer DJ, Frank E (2002). "Placebo in clinical trials for depression: complexity and necessity". JAMA 287 (23): 1853–4. doi:10.1001/jama.287.14.1853. PMID 11939872. 
  11. ^ Spielmans GI (2002). "St John's wort and depression". JAMA 288 (4): 448–9. PMID 12132963. 
  12. ^ Randløv C, Mehlsen J, Thomsen CF, Hedman C, von Fircks H, Winther K (2006). "The efficacy of St. John's Wort in patients with minor depressive symptoms or dysthymia--a double-blind placebo-controlled study". Phytomedicine 13 (4): 215–21. doi:10.1016/j.phymed.2005.11.006. PMID 16423519. 
  13. ^ Kumar V, Mdzinarishvili A, Kiewert C, et al. (September 2006). "NMDA receptor-antagonistic properties of hyperforin, a constituent of St. John's Wort" ([dead link]). J. Pharmacol. Sci. 102 (1): 47–54. doi:10.1254/jphs.FP0060378. PMID 16936454. http://joi.jlc.jst.go.jp/JST.JSTAGE/jphs/FP0060378?from=PubMed. 
  14. ^ Cecchini C, Cresci A, Coman MM, et al. (June 2007). "Antimicrobial activity of seven hypericum entities from central Italy". Planta Med. 73 (6): 564–6. doi:10.1055/s-2007-967198. PMID 17516331. 
  15. ^ Weber, Wendy; Ann Vander Stoep, Rachelle L. McCarty, Noel S. Weiss, Joseph Biederman, Jon McClellan (2008-06-11). "Hypericum perforatum (St John's Wort) for Attention-Deficit/Hyperactivity Disorder in Children and Adolescents". Journal of the American Medical Association 299 (22): 2633–2641. doi:10.1001/jama.299.22.2633. PMID 18544723. http://jama.ama-assn.org/cgi/content/full/299/22/2633. Retrieved on 2009-03-22. 
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  17. ^ Barnes J, Anderson LA, Phillipson JD (2002). Herbal Medicines: A guide for healthcare professionals (2 ed.) London: Pharmaceutical Press. ISBN 0-85369-474-5. Parker, V; Wong, AH; Boon, HS; Seeman, MV (February). "Adverse reactions to St John's Wort.". Canadian Journal of Psychiatry 46 (1): 77–79. http://www.ncbi.nlm.nih.gov/pubmed/11221494. 
  18. ^ Schey KL, Patat S, Chignell CF, Datillo M, Wang RH, Roberts JE (August 2000). "Photooxidation of lens alpha-crystallin by hypericin (active ingredient in St. John's Wort)". Photochem. Photobiol. 72 (2): 200–3. doi:10.1562/0031-8655(2000)072<0200:POLCBH>2.0.CO;2. PMID 10946573. http://www3.interscience.wiley.com/resolve/openurl?genre=article&sid=nlm:pubmed&issn=0031-8655&date=2000&volume=72&issue=2&spage=200. 
  19. ^ Rossi S (Ed.) (2005). Australian Medicines Handbook 2005. Adelaide: Australian Medicines Handbook. ISBN 0-9578521-9-3.
  20. ^ Umek A, Kreft S, Kartnig T, Heydel B.Quantitative phytochemical analyses of six hypericum species growing in slovenia. Planta Med. 1999;65:388-90 [1]
  21. ^ Tatsis EC, Boeren S, Exarchou V, Troganis AN, Vervoort J, Gerothanassis IP.Identification of the major constituents of Hypericum perforatum by LC/SPE/NMR and/or LC/MS. Phytochemistry. 2007;68:383-93. [2]
  22. ^ Schwob I, Bessière JM, Viano J.Composition of the essential oils of Hypericum perforatum L. from southeastern France.C R Biol. 2002;325:781-5.
  23. ^ Leuner K, Kazanski V, Müller M, Essin K, Henke B, Gollasch M, Harteneck C, Müller WE (2007). "Hyperforin--a key constituent of St. John's wort specifically activates TRPC6 channels". FASEB J. 21 (14): 4101–11. doi:10.1096/fj.07-8110com. PMID 17666455. 
  24. ^ Nahrstedt A, Butterweck V (1997). "Biologically active and other chemical constituents of the herb of Hypericum perforatum L". Pharmacopsychiatry 30 Suppl 2: 129–34. doi:10.1055/s-2007-979533. PMID 9342774. 
  25. ^ a b Butterweck V (2003). "Mechanism of action of St John's wort in depression : what is known?". CNS Drugs 17 (8): 539–62. doi:10.2165/00023210-200317080-00001. PMID 12775192. 
  26. ^ Müller WE (2003). "Current St John's wort research from mode of action to clinical efficacy". Pharmacol. Res. 47 (2): 101–9. doi:10.1016/S1043-6618(02)00266-9. PMID 12543057. 
  27. ^ Woelk H (2000). "Comparison of St John's wort and imipramine for treating depression: randomised controlled trial". BMJ 321 (7260): 536–9. doi:10.1136/bmj.321.7260.536. PMID 10968813. 
  28. ^ Schrader E (2000). "Equivalence of St John's wort extract (Ze 117) and fluoxetine: a randomized, controlled study in mild-moderate depression". Int Clin Psychopharmacol 15 (2): 61–8. doi:10.1097/00004850-200015020-00001. PMID 10759336. 
  29. ^ St John's wort

Further reading

  • British Herbal Medicine Association Scientific Committee (1983). British Herbal Pharmacopoeia. West Yorkshire: British Herbal Medicine Association. ISBN 0-903032-07-4

See also

External links


 
 

 

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