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St John's Wort quick review
Botanical description: refers to the species Hypericum perforatum, also known as Hypericum perforatum, klamath weed, John's wort; a yellow-flowering, rhizomatous, perennial herb indigenous to Europe.
Active constituents: hypericin, pseudohypericin, other dianthrones, flavonoids, xanthones, tannins, and hyperforin.
Health benefits: used in the treatment of mild to moderate depression, anxiety, stomach upset, insomnia, fluid retention, and hemorrhoids.

Dosage: the usual dose for mild depression and mood disorders is 500–1,050 mg of St. John's wort extract, three times per day.
Side effects: stomach upset, hives or other skin rash, fatigue, restlessness, headache, dry mouth, and feelings of dizziness or mental confusion.
 
St. John's Wort Extract
People throughout the world rely on St. John's wort for mental well-being. More than 25 double-blind, controlled trials have confirmed this herb's support for stress and mood. Its two unique compounds, hypericins and hyperforin, are key to the extract's potent, beneficial effects. Clinically proven for overall well-being. Promotes positive mood. Click here for more information.
 

St John's Wort


St John's wort used alone refers to the species Hypericum perforatum, also known as Hypericum perforatum, klamath weed, John's wort, amber touch-and-heal, goatweed, rosin rose, and milleperituis. St. John's wort was named after St John's Day which falls on June 24, the approximate flowering season in the northern hemisphere. 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 picture in the house during St John's day. The species name "perforatum" refers to the small windows in the leaves, which can be seen when they are held against the light. St John's wort is a yellow-flowering, rhizomatous, perennial herb indigenous to Europe, which has been introduced to the Americas and grows wild in many meadows. St John's wort is a perennial from underground runners, growing 0.3 to 1 metre in height. Stems are square in cross section with 4 raised lines and leaves about 3/4 inch long, without translucent glandular dots or with few large ones in the upper leaves. The woody, branched root spreads from the base with runners that produce numerous stalks. Flowers are bright yellow with five petals and are about 3/4 inch across. The whole plant above the ground is harvested when the plant is just flowering. The black dots often visible along the petal margins are glands containing hyericin. Both the flowers and leaves are used for medicinal purposes.
 

Active constituents of St John's Wort


The major constituents in St. John's wort include hypericin, pseudohypericin, other dianthrones, flavonoids, xanthones, tannins, and hyperforin. Hyperforin is believed to be the major constituent responsible for antidepressant activity, and has been shown to inhibit the uptake of 5-HTP, dopamine, noradrenaline, GABA and glutamate. Hypericin extract contains at least ten groups of constituents that may contribute to the pharmacological activity of the herb. Hypericin is a napthodianthrone derivative that readily enters the bloodstream and is not broken down in the liver. This compound absorbs sun energy, and when it is fully oxidized turns black in plant tissues.
 

Medicinal uses and health benefits of St John's Wort


St. John's wort has been used as an herbal medicine for centuries, both orally and topically, as an anti-inflammatory, sedative,
analgesic, diuretic, antimalarial, and wound-healing agent. St. John's wort has been used in the treatment of mild to moderate depression, anxiety, stomach upset, insomnia, fluid retention, and hemorrhoids. St. John's wort has also been used topically in the treatment of nerve and muscle pain, skin inflammation, skin wounds, and burns.

St. John's wort has been effective in reducing depressive symptoms in those with mild to moderate but not severe (called major) depression. St. John's wort herb works better than a placebo in the treatment of mild to moderate depression. St. John's wort appears to boost levels of the brain chemical serotonin, which affects the emotions. As an antidepressant, St. John's wort inhibits an enzyme which degrades certain neurotransmitters serotonin, norepinephrine, and dopamine. The herb may also aid in treating depressive elements of chronic fatigue syndrome and seasonal affective disorder.

St. John's wort has been used externally as an anti-inflammatory, astringent, and antiseptic. St. John's wort has been reputed to inhibit replication of several viruses, including the Herpes simplex, HIV, and the virus that causes mononucleosis. St John's Wort has an anti-inflammatory action and helps to stimulate the growth and repair of skin tissue. Applied to the skin, oily preparations of the herb have an antibacterial and anti-inflammatory action. It's particularly effective when applied topically (in the form of an ointment) for the treatment of burns, cuts, scrapes, and minor skin irritations. St. John's wort cream or ointment can soothe the pain of hemorrhoids.

 

Dosage and administration of St John's Wort


St. John's wort is available in capsules, tablets, tinctures, teas, and oil-based skin lotions. Chopped or powdered forms of the dried herb are also available. St. John's wort products should be standardized to contain 0.3% hypericin. The usual dose for mild depression and mood disorders is 500–1,050 mg of St. John's wort extract, three times per day, with meals. To treat inflammation, as in wounds, burns or hemorrhoids, an oil-based preparation of St. John's wort can be applied topically.
 

Side effects, precautions, interactions


St John's wort is generally well tolerated, with an adverse effect profile similar to placebo. Potential side effects include stomach upset, hives or other skin rash, fatigue, restlessness, headache, dry mouth, and feelings of dizziness or mental confusion. St. John's wort interacts with a range of medications. St. John's wort may interact with antidepressant medications that are used to treat depression or other mood disorders. St. John's wort should not be taken by those on digoxin because the herb may decrease levels of the medication and reduce its effectiveness. St John's wort decreases the levels of certain medications in the body thereby decreasing their efficacy. Such medications may include other antidepressants (SSRIs and TCAs), contraceptives, cholesterol-lowering medications, etc. Patients on any medications (including over-the-counter) are advised to consult their pharmacist or physician prior to taking any product containing St John's Wort. St. John's Wort may interact with monoamine oxidase inhibitor drugs, which are used for depression. St. John's Wort may reduce the effects of the cholesterol-lowering drug simvastatin. St. John's wort is not recommended for children, or for women who are pregnant or lactating.