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Quest Vitamins LTD,
8 Venture Way,
Aston Science Park,
B7 4AP.

Tel: 0121 359 0056
Fax: 0121 359 0313
Registered in England No. 2530437

St. John's Wort (Hypericum perforatum)


St. John?s wort is a shrub-like plant with bright yellow flowers. The plant is native to many parts of the world including Europe and the United States and is traditionally used in the care of Wounds.

St. John?s wort is stated to possess sedative (calming / soothing) and astringent properties. The herb has also been used for excitability, neuralgia, fibrositis (muscular rheumatism), Sciatica (Pain in the sciatic nerve - includes the buttock, back of thigh, calf and foot) and for wounds (antibacterial).


Part of the plant used: HERB WITH FLOWERS.

Herb powder, 2-4 g three times daily.


St John?s wort has been used by people who are easily irritated, for nerve Pain, muscular rheumatism, Sciatica and menstrual Anxiety and/or Depression. St John?s Wort is also anti-bacterial against Bordetella pertussis (which gives whooping Cough) and Staphylococcus aureus (Skin Infections and Boils), shigellae and E.coli (1,2). Extracts are antiviral against Influenza (3).

Depression & related conditions
St John?s wort extract is reported to improve symptoms such as Anxiety, Insomnia, and Depression (4). A double-blind trial involving 100 patients showed that this herb was more effective than diazepam (5). Recent studies indicate that St. John?s wort may relieve depression symptoms by blocking the reuptake of the neurotransmitters serotonin, norepinephrine, and dopamine (6). These neurotransmitters become more available to the brain. Hyperforin, a consituent of St. John?s wort, may be reponsible for this action (7). St. John?s Wort may also help alleviate seasonal affective disorder (SAD).

Studies have shown that the flavonoid fraction of St John?s Wort is analgesic (8).

The "amento-flavone" fraction on St. John?s wort is anti-inflammatory and anti-ulcer (9). One study noted a 90% reduction in Pain from gastroduodenitis (Inflammation of the upper bowel).

St John?s wort is calming/sedative. This has been attributed to the biflavonoid fraction. Hypericin can also calm the nervous system (10).

St John?s wort has also been effective for treatment of the Skin disorder Vitiligo (10).


Photosensitivity of the Skin has been noted in certain individuals following the ingestion of an herbal tea made from the leaves. The volatile oil of St. John?s wort is irritant.

Pregnant and lactating women should consult with a qualified health professional prior to taking St. John?s wort.

St. John?s wort is not recommended for use by children.


St. John?s wort should not be taken by those on medication for Depression. Excessive doses may potentiate existing therapies (such as MAOI - monoamine oxidase inhibitor drugs) and may cause an allergic reaction in sensitive individuals. St. John?s wort may also interact with serotonin reuptake inhibitor (SSRI) drugs, e.g. Prozac.

St. John's wort has been shown to increase the activity of a group of liver enzymes involved in the metabolism of a number of prescribed drugs. The drugs in question are theophylline (a bronchodilator), cyclosporin (an immune suppressant), indinavir (anti-viral therapy for HIV), warfarin, digoxin, and the contraceptive pill. People taking these drugs should consult with their doctor or pharmacist before taking a St. John's wort product, as the herb may reduce their effectiveness.


1. Sakar MK et al. Antimicrobial activities of some hypericum species growing in Turkey. Fitotherapie, 59:49-52, 1988.
2. Zakharova NS et al. Action of plant extracts on the natural immunity indices of animals. Zh Mikrobiol Epidemiol Immunobiol, ,3:75-78, 1986.
3. Mishenkova EL et al. Antiviral properties of St John's Wort and preparations produced from it. Tr S?ezda Mikrobiol Ukr,:222-223, 1975.
4. M?ldner VH, Z?ller M. Antidrepressive effect of a hypericum extract standardised to the active hypericine complex/biochemistry and clinical studies. Arzneimittelforschung, 34:918, 1984.
5. Panijel M. Die behandlung mittlshwerer angstzust?nde. Therapewoche, 41:4659-4668, 1985.
6. M?ller WE, Rolli M, Sch?fer C, Hafner U. Effects of hypericum extract (LI 160) in biochemical models of antidepressant activity. Pharmacopsychiatry 1997;30(suppl):102-7.
7. M?ller WE, Singer A, Wonnemann M, et al. Hyperforin represents the neurotransmitter reuptake inhibiting constituent of hypericum extract. Pharmacopsychiatry 1998;31(suppl):16-21.
8. Vasilchenko EA et al Analgesic action of flavonoids of Rhododendron luteum Sweet, hypericum perforatum L., Lespedeza bicolor Turcz and L. hedysaroides (Pall.) Kitag. Rastit Resur, 22:12-21, 1986.
9. Bergh?fer R, H?lzl J. Isolation of I3',II8-biapigenin (amentoflavone) from hypericum perforatum. Planta Med, 5:91, 1989.
10. "Herbal Medicines A Guide to Health-Care Professionals", C A Newall, L A Anderson, J D Phillipson, The Pharmaceutical Press, 1996.

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