St. John's wort (Hypericum perforatum L.)

• Background
• Related terms
• Evidence
• Dosing
• Safety
• Methodology
• Selected references

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St. John's wort (Hypericum perforatum L.)

Background

Extracts of Hypericum perforatum L. (St. John's wort) have been recommended traditionally for a wide range of medical conditions. The most common modern-day use of St. John's wort is the treatment of depression. Numerous studies report St. John's wort to be more effective than placebo and equally effective as tricyclic antidepressant drugs in the short-term treatment of mild-to-moderate major depression (1-3 months). It is not clear if St. John's wort is as effective as selective serotonin reuptake inhibitor (SSRI) antidepressants such as sertraline (Zoloft®).

Recently, controversy has been raised by two high-quality trials of St. John's wort for major depression that did not show any benefits. However, due to problems with the designs of these studies, they cannot be considered definitive. Overall, the scientific evidence supports the effectiveness of St. John's wort in mild-to-moderate major depression. The evidence in severe major depression remains unclear.

St. John's wort can cause many serious interactions with prescription drugs, herbs, or supplements. Therefore, people using any medications should consult their healthcare providers including their pharmacist prior to starting therapy.

Related terms

Amber touch-and-heal, balm-of-warrior's wound, balsana, bassant, Blutkraut, bossant, Calmigen®, corancillo dendlu, devil's scorge, Eisenblut, flor de São João, fuga daemonum, goatweed hartheu, heofarigo on, herba de millepertius, herba hyperici, herrgottsblut, hexenkraut, hierba de San Juan, hipericão, hipérico, hipericon, HP, isorhamnetin, Jarsin, Johanniskraut, klammath weed, Liebeskraut LI 160, lord God's wonder plant, millepertius pelicao, perforate, pinillo de oro, PM235, pseudohypericin, rosin rose, SJW extract LI 160, St. John's wort WS 5572, STW 3-VI, tenturotou, Teufelsflucht, touch and heal, Walpurgiskraut (German), witcher's herb, WS 5572.

Evidence

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Grading rationale

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Abdominal discomfort or irritation, abrasions (topical), alcoholism, allergies, anti-inflammatory, anti-malarial, antioxidant, antiviral, asthma, athletic performance enhancement, bacterial skin infections (topical), bedwetting, benzodiazepine withdrawal, bruises (topical), burns (topical), cancer, chronic bowel irritation, chronic ear infections, colitis, contusions, dental pain, diarrhea, diuretic (increasing urine flow), dyspepsia, Epstein-Barr virus infection, fatigue, glioma (brain tumor), heartburn, hemorrhoids, herpes virus infection, hypnotic, immune function, influenza, insomnia, joint pain, liver protection from toxins, malaria treatment, menstrual pain, mood disorders (menopause), nicotine withdrawal, rheumatism, skin scrapes, sleep, snakebites, sprains, substance abuse, ulcers, weight loss, wound healing (topical).

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (over 18 years old)

Clinical trials have used a range of doses, including 0.17-2.7 milligrams of hypericin by mouth, and 900-1,800 milligrams of St. John's wort extract daily by mouth.

1.5% hyperforin (verum) has been applied to the skin for the treatment of atopic dermatitis.

Children (under 18 years old)

Clinical trials have used 150-1,800 milligrams of St. John's wort extract daily by mouth with good tolerability.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Infrequent allergic skin reactions, including rash and itching, are reported in human studies.

Side Effects and Warnings

In published studies, St. John's wort has generally been well tolerated at recommended doses for up to 1-3 months. The most common adverse effects include gastrointestinal upset, skin reactions, fatigue/sedation, restlessness or anxiety, sexual dysfunction (including impotence), sensitivity to light, dizziness, headache, and dry mouth. Several recent studies suggest that side effects occur in one to three percent of patients taking St. John's wort, and that the number of adverse events may be similar to placebo (and less than standard antidepressant drugs). Animal toxicity studies have found only non-specific symptoms such as weight loss. One small study reported elevated thyroid stimulating hormone (TSH) levels to be associated with taking St. John's wort.

It has been reported that St. John's wort may cause psychiatric symptoms such as suicidal and homicidal thoughts.

Delayed ejaculation has been reported in animal studies.

Pregnancy and Breastfeeding

There is not enough scientific evidence available to recommend use during pregnancy or breastfeeding.

Methodology

This patient information is based on a professional level monograph edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Monograph methodology

Selected references

1. Briese V, Stammwitz U, Friede M, et al. Black cohosh with or without St. John's wort for symptom-specific climacteric treatment--results of a large-scale, controlled, observational study. Maturitas 2007 Aug 20;57(4):405-14.
2. Chung DJ, Kim HY, Park KH, et al. Black cohosh and St. John's wort (GYNO-Plus) for climacteric symptoms. Yonsei Med J 2007 Apr 30;48(2):289-94.
3. Franklin M, Hafizi S, Reed A, et al. Effect of sub-chronic treatment with Jarsin (extract of St John's wort, Hypericum perforatum) at two dose levels on evening salivary melatonin and cortisol concentrations in healthy male volunteers. Pharmacopsychiatry 2006 Jan;39(1):13-5.
4. Kasper S, Volz HP, Moller HJ, et al. Continuation and long-term maintenance treatment with Hypericum extract WS 5570 after recovery from an acute episode of moderate depression--a double-blind, randomized, placebo controlled long-term trial. Eur Neuropsychopharmacol 2008;18(11):803-813.
5. Linde K, Berner MM, Kriston L. St John's wort for major depression. Cochrane Database Syst Rev 2008;(4):CD000448.
6. Muller T, Mannel M, Murck H, et al. Treatment of somatoform disorders with St. John's wort: a randomized, double-blind and placebo-controlled trial. Psychosom Med 2004;66(4):538-547.
7. Murphy PA, Kern SE, Stanczyk FZ, et al. Interaction of St. John's Wort with oral contraceptives: effects on the pharmacokinetics of norethindrone and ethinyl estradiol, ovarian activity and breakthrough bleeding. Contraception 2005 Jun;71(6):402-8.
8. Randlov C, Mehlsen J, Thomsen CF, et al. The efficacy of St. John's Wort in patients with minor depressive symptoms or dysthymia--a double-blind placebo-controlled study. Phytomedicine 2006 Mar;13(4):215-21.
9. Saarto T, Wiffen PJ. Antidepressants for neuropathic pain. Cochrane Database Syst Rev. 2007 Oct 17;(4):CD005454.
10. Sardella A, Lodi G, Demarosi F, et al. Hypericum perforatum extract in burning mouth syndrome: a randomized placebo-controlled study. J Oral Pathol Med 2008;37(7):395-401.
11. Schempp CM, Windeck T, Hezel S, et al. Topical treatment of atopic dermatitis with St. John's wort cream--a randomized, placebo controlled, double blind half-side comparison. Phytomedicine 2003;10 Suppl 4:31-37.
12. Schulz V. Safety of St. John's Wort extract compared to synthetic antidepressants. Phytomedicine 2006 Feb;13(3):199-204.
13. Shelton RC, Keller MB, Gelenberg A, et al. Effectiveness of St John's wort in major depression: a randomized controlled trial. JAMA 4-18-2001;285(15):1978-1986.
14. Uebelhack R, Blohmer JU, Graubaum HJ, et al. Black cohosh and St. John's wort for climacteric complaints: a randomized trial. Obstet Gynecol 2006 Feb;107(2 Pt 1):247-55.
15. Weber W, Vander Stoep A, McCarty RL, et al. Hypericum perforatum (St John's wort) for attention-deficit/hyperactivity disorder in children and adolescents: a randomized controlled trial. JAMA 6-11-2008;299(22):2633-2641.

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