Home Up Chinese Medicine Conditions Drug Interactions Health Care Directory Alt Med Books Hormone Replacement Articles FAQs Health Resources Supplements Therapies Natural Products Medical Terms Site Map About Us The MAY Foundation


St. John's wort once was thought to rid the body of evil spirits, but more recently it has been used to treat problems such as depression, anxiety, and sleeplessness. When steeped in oil and applied to the skin, it helps heal wounds and burns. Research suggests it may also be useful in treating infections caused by viruses.

Here are some illnesses and conditions that St. John's wort has been used to treat:

bulletDepression. St. John's wort reduces symptoms of depression in people with mild to moderate forms of the condition.
bulletSeasonal affective disorder. Used alone, St. John's wort improves mood. Effects are even greater when the herb is used in combination with light therapy.
bulletOther mood problems. St. John's wort helps reduce anxiety, listlessness, and feelings of worthlessness.
bulletSleep problems. The herb relieves sleeplessness (insomnia) and the tendency to sleep too long (hypersomnia).
bulletHIV infection and AIDS. Research and patients' experiences suggest St. John's wort may improve the health of people infected with human immunodeficiency virus (HIV), the virus that causes AIDS.
bulletWounds and burns. In forms that can be applied to the skin, St. John's wort reduces pain and inflammation and promotes healing.
bulletHemorrhoids. "Red oil," a preparation made by steeping St. John's wort flowers in oil, eases discomfort when applied to hemorrhoids.

Plant Description

St. John's wort is a shrubby plant with clusters of yellow flowers. The plant is often in full bloom around June 24, the day traditionally celebrated as the birthday of John the Baptist. Both the flowers and leaves are used as medicine.

What's It Made Of?

The best-studied active components are hypericin and pseudohypericin, found in both the leaves and flowers. There has been recent research to suggest that these best-studied components may not be the most active in the plant, with significant debate ensuing within the industry. It also includes other components such as essential oils and flavonoids.

Available Forms

You can buy St. John's wort in many forms: capsules, liquids, oil-based skin lotions, and teas. You can also buy chopped or powdered forms of the dried herb. Look for products that are standardized to contain 0.3% hypericin.

How to Take It

When taken by mouth for depression and other mood problems, the usual dose is 300 to 500 mg at 0.3 percent, three times a day, with meals, for a minimum of four to six weeks. You can also make a tea by steeping 1 to 2 tsp. of dried St. John's wort in a cup of boiling water for 10 minutes. Drink 1 to 2 cups a day for four to six weeks. But keep in mind that the dose you get when you make St. John's wort tea may not be as consistent as what you get in capsules or other products.

For treating wounds, burns or hemorrhoids, use an oil-based preparation of St. John's wort that you can rub onto your skin.


bulletDepression is a serious condition. If your depression is severe or if you feel like hurting yourself or someone else, see a health care professional before using St. John's wort. There are some conditions that you should not try to treat yourself with herbs or other over-the-counter medicines. A health care professional can help you decide whether St. John's wort is right for you.
bulletDo not take St. John's wort if you are pregnant or breast-feeding.
bulletSt. John's wort may make your skin unusually sensitive to sunlight. Although this reaction is rare, you should be careful about sun exposure if you have fair skin or if you are taking St. John's wort in large doses or over a long time. Use a sunscreen with a skin protection factor (SPF) of at least 15, and do not use sunlamps, tanning booths or tanning beds.

Side effects of St. John's wort are usually mild and may include:

bulletAbdominal pain, bloating, constipation
bulletNausea, vomiting
bulletDry mouth
bulletItching, hives, skin rash
bulletSleep problems
bulletElevated blood pressure
bulletUnusual tiredness

Possible Interactions

Using St. John's wort with antiviral agents like indinavir and other protease inhibitors is not recommended. There is the possibility of an interaction between this herb and these medications that could undermine the effectiveness of the antiviral medications.

St. John's wort may interact with antidepressant medication that are used to treat depression or other mood disorders. Therefore, do not take this herb with any such medications.

You should not take St. John's wort if you are taking the heart medication digoxin because of the potentially dangerous interaction between this herb and this medication.

You should not take this herb with immunosuppressive medications like cyclosporin because it may reduce the effectiveness of these medications.

There have also been reports of bleeding in women taking St. John's wort with birth control medications. The interaction between St. John's wort and birth control medications may result in decreased effectiveness of these medications.

Supporting Research

Bombardelli E, Morazzoni P. Hypericum perforatum. Fitoterapia. 1995;LXVI:43–68.

Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, Ore: Eclectic Medical; 1998:123-125.

Brown R. Potential interactions of herbal medicines with antipsychotics, antidepressants, and hypnotics. Eur J Herb Med. 1997;3(2):25–28.

Degar S, et al. Inactivation of the human immunodeficiency virus by hypericin: Evidence for phytochemical alterations of p24 and a block in uncoating. AIDS Res Hum Retroviruses. 1992;8:1929–1936.

De Smet P, Peter AGM, Nolen WA. St. John's wort as an antidepressant. Br Med J. 1996;313:241–247.

D'Arcy PF. Adverse reactions and interactions with herbal medicines. Adv Drug React Toxicol Rev. 1993;12(3):147–162.

Furner V, Bek M, Gold JA. A phase I/II unblinded dose ranging study of hypericin in HIV-positive subjects. Int Conf AIDS. 1991;7:199.

Cott JM. In vitro receptor binding and enzyme inhibition by Hypericum perforatum extract. Pharmacopsychiatry. 1997;30(suppl 2):108–112.

Gulick R, et al. Human hypericism: A photosensitivity reaction to hypericin (St. John's wort). Int Conf AIDS. 1992; 8:B90.

Hardman JG, Limbird LE, Molinoff PB, et al. Goodman and Gilman's The Pharmacological Basis of Therapeutics. 9th ed. New York, NY: Pergamon Press; 1996.

Heiligenstein E, Guenther G. Over-the-counter psychotropics: a review of melatonin, St John's wort, valerian, and kava kava. J Am Coll Health. 1998;46(6):271–276.

Hippius H. St John's wort (Hypericum perforatum)—an herbal antidepressant. Curr Med Res Opin. 1998;14(3):171–184.

Holz J, Demisch L, Gollnik B. Investigations about antidepressive and mood changing effects of Hypericum perforatum. Planta Med. 1989;55:643.

Johne A, Brockmoller J, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatun). Clinical Pharmacology & Therapeutics 1999;66:338-45.

Lavie G, et al. Studies of the human mechanism of action of the antiviral agents hypericin and pseudohypericin. Proc Natl Acad Sci USA. 1989;86:5963–5967.

Lieberman S. Nutraceutical review of St. John's wort (Hypericum perforatum) for the treatment of depression. J Women's Health. 1998;7(2):177–182.

Linde K, Ramirez G, Mulrow CD, et al. St. John's wort for depression: an overview and meta-analysis of randomised clinical trials. BMJ. 1996;313:253–257.

Martinez B, Kasper S, Ruhrmann S, Moller HJ. Hypericum in the treatment of seasonal affective disorders. J Geriatr Psychiatry Neurol. 1994;7(Suppl 1):S29–33.

McGuffin M, Hobbs C, Upton R, et al, eds. Botanical Safety Handbook . Boca Raton, Fla: CRC Press; 1997.

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 USA. 1988;85:5230–5234.

Miller LG. Herbal medicinals: selected clinical considerations focusing on known or potential drug-herb interactions. Arch Intern Med. 1998;158(20):2200–2211.

Muller WE, Rolli M, Schafer C, Hafner, U. Effects of hypericum extract (LI 160) in biochemical models of antidepressant activity. Pharmacopsychiatry. 1997;30(suppl):102–107.

Murray MT. Common questions about St. John's wort extract. Am J Natural Med. 1997;4(7):14–19.

Murray MT. The Healing Power of Herbs: The Enlightened Person's Guide to the Wonders of Medicinal Plants. Rocklin, Calif: Prima Publishing; 1995.

Nebel A, Schneider BJ, Baker RK, et al. Potential metabolic interaction between St. John's wort and theophylline. Ann Pharmacother. 1999;33:502.

Nordfors M, Hartvig P. St. John's wort against depression in favor again [in Swedish]. Lakartidningen. 1997;94(25):2365–2367.

Okpanyi SN, Weischer ML. Experimental animal studies of the psychotropic activity of the Hypericum extract. Arzneim-Forsch. 1987;37:10–13.

Perovic S, Muller WEG. Pharmacological profile of Hypericum extract: effect on serotonin uptake by postsynaptic receptors. Arzneim-Forsch. 1995;45:1145–1148.

Piscitelli S, Burstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort [letter]. Lancet. 2000;355:547-548.

Rasmussen P. St. John's wort: a review of its use in depression. Australian Journal of Medical Herbalism. 1998;10:8–13.

Reichert R. St John's wort extract as a tricyclic medication substitute for mild to moderate depression. Quart Rev Nat Med. 1995;Winter:275–278.

Ruschitzka F, Meier PJ, Turina M, et al. Acute heart transplant rejection due to Saint John's wort. Lancet. 2000,355. Available at

Sparenburg B, Demisch L, Hoezl J. Antidepressant constituents of St. John's wort. PZ Wiss. 1993;6:50–54.

Tyler VE. The Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies. Binghamton, NY: Pharmaceutical Products Press; 1993.

Wagner H, Bladt S. Pharmaceutical quality of hypericum extracts. J Geriatr Psychiatry Neurol. 1994;(suppl 1):S65–S68.

Woelk H, Burkhard G, Grunwald J. Benefits and risks of the hypericum extract LI 160: drug monitoring study with 3250 patients. J Geriatr Psychiatry Neurol. 1994;(suppl 1):S34–S38.

Yue Q, Bergquist C, Gerden B. Safety of St. John's wort (Hypericum perforatum) [letter]. Lancet. 2000;355:576-577.

Copyright © 2000 Integrative Medicine Communications

The publisher does not accept any responsibility for the accuracy of the information or the consequences arising from the application, use, or misuse of any of the information contained herein, including any injury and/or damage to any person or property as a matter of product liability, negligence, or otherwise. No warranty, expressed or implied, is made in regard to the contents of this material. No claims or endorsements are made for any drugs or compounds currently marketed or in investigative use. This material is not intended as a guide to self-medication. The reader is advised to discuss the information provided here with a doctor, pharmacist, nurse, or other authorized healthcare practitioner and to check product information (including package inserts) regarding dosage, precautions, warnings, interactions, and contraindications before administering any drug, herb, or supplement discussed herein