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St. John's wort (Hypericum perforatum L.)
Generic Name: st. john's wort
CategoryHerbs & Supplements
Amber touch-and-heal, balm-of-warrior's wound, balsana, bassant, Blutkraut, bossant, Calmigen®, corancillo dendlu, devil's scorge, Eisenblut, flor de Sao Joa, fuga daemonum, goatweed hartheu, heofarigo on, herba de millepertius, herba hyperici, herrgottsblut, hexenkraut, hierba de San Juan, hipericao, hiperico 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 (Dutch), witcher's herb, WS 5572.
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.
EvidenceDISCLAIMER: 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.
Depressive disorder (mild-to-moderate):
St. John's wort has been extensively studied in Europe over the last two decades, with more recent research in the United States. Short-term studies (1-3 months) suggest that St. John's wort is more effective than placebo (sugar pill), and equally effective as tricyclic antidepressants (TCAs) in the treatment of mild-to-moderate major depression. Comparisons to the more commonly prescribed selective serotonin reuptake inhibitor (SSRI) antidepressants, such as fluoxetine (Prozac®) or sertraline (Zoloft®), are more limited. However, other data suggest that St. John's wort may be just as effective as SSRIs with fewer side effects. Safety concerns exist as with most conventional and complementary therapies.
Overall, there is currently not enough evidence to recommend St. John's wort for the primary treatment of anxiety disorders.
Early study of hypericum-cream in the topical treatment of mild to moderate atopic dermatitis shows positive results. Further studies are needed before a firm recommendation can be made.
Depressive disorder (severe):
Studies of St. John's wort for severe depression have not provided clear evidence of effectiveness.
Early study shows that St. John's wort may help neuropathic (nerve) pain. Further research is needed to confirm these results.
Obsessive-compulsive disorder (OCD):
There are a few reported cases of possible benefits of St. John's wort in patients with obsessive-compulsive disorder (OCD). Currently there is not enough scientific evidence to recommend St. John's wort for this condition.
There is currently not enough scientific evidence to recommend St. John's wort for this indication.
Seasonal affective disorder (SAD):
Despite some promising early data, there is currently not enough evidence to recommend St. John's wort for depressive disorder with seasonal pattern or Seasonal Affective Disorder (SAD).
Somatoform disorders show physical symptoms that cannot be attributed to organic disease and appear to be of psychic origin. Early evidence shows that St. John's wort may help with somatoform disorders. Further research is needed to confirm these results.
Human immunodeficiency virus (HIV):
Anti-viral effects of St. John's wort have been observed in laboratory studies, but were not found in one human study. Multiple reports of significant adverse effects and interactions with drugs used for HIV/AIDS, including protease inhibitors (PIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), suggest that patients being treated for HIV/AIDS should avoid this herb. Therefore, there is evidence to recommend against using St. John's wort in the treatment of patients with HIV/AIDS.
Results of early study on the efficacy of St. John's wort in social phobia do not show benefit. More study is needed to confirm these findings.
TraditionWARNING: DISCLAIMER: The below uses are based on tradition, scientific theories, or limited research. 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. There may be other proposed uses that are not listed below.
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)
There is not enough scientific data to recommend St. John's wort in children.
SafetyDISCLAIMER: Many complementary techniques are practiced by healthcare professionals with formal training, in accordance with the standards of national organizations. However, this is not universally the case, and adverse effects are possible. Due to limited research, in some cases only limited safety information is available.
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), 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
Interactions with Drugs
St. John's wort interferes with the way the body processes many drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be increased in the blood in the short-term (causing increased effects or potentially serious adverse reactions) and/or decreased in the blood in the long-term (which can reduce the intended effects). Examples of medications that may be affected by St. John's wort in this manner include carbamazepine, cyclosporin, irinotecan, midazolam, nifedipine, simvastatin, theophylline, warfarin, or HIV drugs such as non-nucleoside reverse transcriptase inhibitors (NNRTIs) or protease inhibitors (PIs). The U.S. Food & Drug Administration (FDA) suggests that patients with HIV/AIDS on protease inhibitors or non-nucleoside reverse transcriptase inhibitors avoid taking St. John's wort.
Taking St. John's wort with antidepressants may lead to increased side effects, including serotonin syndrome and mania. Serotonin syndrome is a condition defined by muscle rigidity, fever, confusion, increased blood pressure and heart rate, and coma. Mania is defined by symptoms of elevated or irritable mood, rapid speech or thoughts, increased activity, and decreased need for sleep. Using St. John's wort with MAOIs may also increase the risk of severely increased blood pressure. Cautious is also advised when using St. John's wort with tricyclic antidepressants.
Reports exist of altered menstrual flow, bleeding, and unwanted pregnancies in women taking birth control pills and St. John's wort at the same time. Although cases of interaction are rare, caution is advised when taking St. John's wort and coumarin-type anticoagulants (blood thinners). In general, individuals should check the package insert and speak with a qualified healthcare professional including a pharmacist about possible interactions with St. John's wort.
St. John's wort may lead to increased risk of sun sensitivity when taken with other drugs such as antibiotics or birth control pills. A possible interaction with loperamide (Imodium®) has been reported; confusion and agitation occurred in one patient taking St. John's wort, loperamide, and the herb valerian (Valeriana officinalis). St. John's wort may interact with triptan-type headache medications. Examples include naratriptan (Amerge®), rizatriptan (Maxalt®), sumatriptan (Imitrex®), and zolmitriptan (Zomig®). In theory, St. John's wort may also interact with certain chemotherapy drugs such as anthracyclines. St. John's wort may increase the anti-inflammatory effects of COX2 inhibitor drugs like Vioxx® or NSAIDS like ibuprofen (Motrin®).
St John's wort may increase imatinib clearance. Thus, patients taking imatinib should avoid taking St John's wort. Concomitant use of enzyme inducers, including St John's wort, may necessitate an increase in the imatinib dose to maintain effectiveness.
In higher doses, St. John's wort has been shown to decrease the blood concentrations of omeprazole, tolbutamide, caffeine, dextromethorphan, fexofenadine, carbamazepine, and cimetidine, among other medications. No relevant interaction has been seen with alprazolam, caffeine, tolbutamide, and digoxin by treatment with a low-hyperforin St. John's wort extract.
Caution is also advised when taking benzodiazepine tranquilizers, opioids, P-glycoprotein regulated drugs, antibiotics, antivirals, anesthetics, antifungals, sedatives, or drugs used for anxiety, heart problems, or seizures. In general, individuals should check the package insert and speak with a qualified healthcare professional including a pharmacist about possible interactions with St. John's wort.
Interactions with Herbs and Dietary Supplements
St. John's wort may interfere with the way the body processes certain herbs and supplements using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be increased in the blood in the short-term, causing increased effects or potentially serious adverse reactions, or decreased in the blood in the long-term, which can reduce the intended effects.
Taking St. John's wort with herbs or supplements with antidepressant activity may lead to increased side effects, including serotonin syndrome, mania, or severe increase in blood pressure. There is a particular risk of these interactions occurring with agents that possess possible monoamine oxidase inhibitory properties.
St. John's wort may lead to increased risk of sun sensitivity when taken with capsaicin or other photosensitizing products. St. John's wort may interact with herbs that also possess cardiac glycoside properties and decrease blood levels.
A possible interaction with the herb valerian (Valeriana officinalis) has been reported; confusion and agitation occurred in one patient taking St. John's wort, loperamide (Immodium®) and valerian. However, St. John's wort and valerian are often used together, with few reported of adverse events. In theory, due to the presence of tannins, St. John's wort may inhibit the absorption of iron.
Although cases of interaction are rare, caution is advised when taking St. John's wort and herbs and supplements that may have blood-thinning effects.
Caution is also advised when taking red yeast rice or any herb or supplements that is P-glycoprotein regulated. In general, individuals should speak with a qualified healthcare professional, including a pharmacist, about possible interactions with St. John's wort.
Use cautiously when combining St. John's wort with herbs or supplements that have the following proposed effects: antibacterial, antiviral, or sedative. Also, St. John's wort may have a possible interaction with herbs or supplements used for anxiety, heart problems, or seizures.
This information is based on a professional level monograph edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com): E-P Barrette, MD (Case Western Reserve University School of Medicine); Ethan Basch, MD (Memorial Sloan-Kettering Cancer Center); Samuel Basch, MD (Mt. Sinai School of Medicine); Steve Bent, MD (University of California San Francisco); Heather Boon, BScPhm, PhD (University of Toronto); Dawn Costa, BA, BS (Natural Standard Research Collaboration); Edzard Ernst, MD, PhD, FRCP (University of Exeter); Ivo Foppa, MD, ScD (Harvard School of Public Health); Paul Hammerness, MD (Massachusetts General Hospital); Jenna Hollenstein, MS, RD (Natural Standard Research Collaboration); Adrianne Rogers, MD (Boston University); Shaina Tanguay-Colucci, BS (Natural Standard Research Collaboration); Catherine Ulbricht, PharmD (Massachusetts General Hospital); Wendy Weissner, BA (Natural Standard Research Collaboration).
BibliographyDISCLAIMER: Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.
Behnke K, Jensen GS, Graubaum HJ, et al. Hypericum perforatum versus fluoxetine in the treatment of mild to moderate depression. Adv Ther 2002;19(1):43-52.
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.
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.
Fava M, Alpert J, Nierenberg AA, et al. A Double-blind, randomized trial of St John's wort, fluoxetine, and placebo in major depressive disorder. J Clin Psychopharmacol 2005 Oct;25(5):441-7.
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.
Hammerness P, Basch E, Ulbricht C, et al. St John's wort: a systematic review of adverse effects and drug interactions for the consultation psychiatrist. Psychosomatics 2003;44(4):271-282.
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.
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.
Philipp M, Kohnen R, Hiller KO. Hypericum extract versus imipramine or placebo in patients with moderate depression: randomised multicentre study of treatment for eight weeks. BMJ 12-11-1999;319(7224):1534-1538.
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.
Saarto T, Wiffen PJ. Antidepressants for neuropathic pain. Cochrane Database Syst Rev. 2007 Oct 17;(4):CD005454.
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.
Schulz V. Safety of St. John's Wort extract compared to synthetic antidepressants. Phytomedicine 2006 Feb;13(3):199-204.
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.
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.
Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.