Consumer Guide To St. John's Wort

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What is St. John's Wort?

This common North American and European perennial has been used by herbalists since antiquity, as a topical wound and burn healer and an oral remedy to treat diarrhea, menstrual disorders, nerve pain, fevers, and other conditions. A number of recent, well-controlled studies indicate that St. John's Wort (Hypericum perforatum) extracts may alleviate symptoms of mild-to-moderate depression. St. John's Wort exerts potent inhibitory effects on HIV (the AIDS virus) and other retroviruses, both in animal tests and in test tube studies on human blood, but is not proven to work against HIV in people—in fact, it can interfere with certain drugs anti-HIV drugs. (Please see "Safety," below)

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Modern perspective

St. John's Wort's traditional use for depression, insomnia, and anxiety inspired German research starting in the 1980's, with findings that brought the herb broader fame in the late 1990's. St. John's Wort also exerts potent inhibitory effects on HIV (the AIDS virus) and other retroviruses, both in animal tests and in isolated human blood.
A number of recent, well-controlled studies indicate that St. John's Wort extracts may significantly relieve symptoms of mild-to-moderate depression. In an analysis of St. John's Wort studies published in 1996, researchers combined the results from 23 randomized clinical trials that tested 1,757 subjects with mild to moderately severe depression. This pooling of studies or "meta-analysis" determined that St. John's Wort is much more effective than a placebo and provokes response rates that are similar to or even slightly better than conventional antidepressants. Current research also indicates that St. John's Wort is better tolerated than conventional antidepressants. Note: St. John's Wort's antidepressant effects may not be apparent until it is taken daily for three weeks or more.

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Benefits and Uses

Shaker communities of the mid-nineteenth century sold the leaves and flowers as a remedy for "low spirits." Herbalists have also used St. John's Wort as a topical wound and burn healer and an oral remedy to treat diarrhea, menstrual disorders, nerve pain, fevers, and other conditions.

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Do Scientists Know How It Works?

Biochemists have identified biologically active compounds with the potential to boost immunity, heal wounds, and counter bacteria and viruses. The fresh plant has low levels (0.1 to 0.3 percent) of the reddish pigment hypericin, plus a number of other compounds, including flavonoids, xanthones, tannins, and alkaloids.
St. John's Wort's effect on the nervous system may be caused by alterations in serotonin, dopamine, or melatonin levels in the body. Hypericin is antiviral and possibly also mood-brightening, although a 1998 clinical study using standard depression rating scales indicated that a compound called hyperforin may be the primary antidepressant constituent.

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Safety

St. John's Wort is generally considered safe, with some exceptions:

• The most common side effects from taking St. John's Wort include nausea, stomach ache, lack of appetite, and tiredness.
• A minuscule percentage of people taking high daily doses of St. John's Wort may experience increased skin reactivity to light from the sun.
• St. John's Wort should not be taken by pregnant women.
• Because the herb's effects on the nervous system remain unclear, most experts recommend against combining it with anti-depressant drugs, including MAOI's, SRRI's (Prozac, Zoloft, etc.), and tricyclics.
• St. John's Wort sharply reduces the effectiveness of anti-HIV protease inhibitors (indinavir, etc.), and the organ transplant drug cyclosporin, and should never be taken with drugs of these types.

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Type Of Products

St. John's Wort is usually sold dried and in capsules, concentrated drops, tinctures, and extracts. Many capsules are standardized extracts containing 0.3 percent hypericin.

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References

• Hansgen, K.D., et al., "Multicenter double-blind study examining the antidepressant effectiveness of the hypericum extract LI 160," Journal of Geriatric Psychiatry and Neurology (1994), 7 Suppl 1:S15?18.
• Harrer, G., and H. Sommer, "Treatment of mild/moderate depressions with hypericum," Phytomedicine (1994), 1:3?8.
• Hobbs, Christopher, "St. John's Wort," HerbalGram (1989), 18/19:24?33
• Holzl, J., et al., "Investigations about antidepressive and mood changing effects of Hypericum perforatum," Planta Medica (1989), 55:643
• Hubner, W.D., "Hypericum treatment of mild depressions with somatic symptoms," Journal of Geriatric Psychiatry and Neurology (1994), 7 Suppl 1:S12?14.
• Hudson JB, Harris L, Towers GH. The importance of light in the anti-HIV effect of hypericin. Antiviral Res 1993 Feb;20(2):173- 8.
• Laakmann G, et al. St. John's wort in mild to moderate depression: the relevance of hyperforin for the clinical efficacy. Pharmacopsychiatry. 1998 Jun;31 Suppl 1:54-9.
• Linde, K., et al., "St. John's Wort for depression: An overview and meta-analysis of randomised clinical trials," British Medical Journal (1996), 313:253?58
• Meruelo D, Lavie G, Lavie D. Therapeutic agents with dramatic antiretroviral activity and little toxicity at effective doses: aromatic polycyclic diones hypericin and pseudohypericin. Proc Natl Acad Sci U S A 1988 Jul;85(14):5230-4.
• Muldner, V.H., and M. Zoller, "Antidepressive effect of a hypericum extract standardized to an active hypericin complex," Arzneimittel-Forschung (1984), 34(8):918?20.
• Reuter, H. D., "Psychotropic herbal drugs: Results of recent pharmacological clinical studies with Hypericum perforatum," presentation at the Second International Conference on Phytotherapeutics, National Herbalists Association of Australia, March 1995, Sidney.
• Schinazi RF, et al. Anthraquinones as a new class of antiviral agents against human immunodeficiency virus. Antiviral Res 1990 May;13(5):265-72.
• Suzuki, O., et al., "Inhibition of monoamine oxidase by hypericin," Planta Medica (1984), 50:272?74.
• Takahashi I, et al. Hypericin and pseudohypericin specifically inhibit protein kinase C: possible relation to their antiretroviral activity. Biochem Biophys Res Commun 1989 Dec 29;165(3):1207-12.
• Vlietinck AJ, et al. Plant-derived leading compounds for chemotherapy of human immunodeficiency virus (HIV) infection. Planta Med 1998 Mar;64(2):97-109.

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