Health Library

St. John's Wort

Introduction

St. John’s wort is a plant with bright yellow flowers. The flowers have been used to ease symptoms of depression and menopause. St. John’s wort has also been applied as an ointment to help promote healing in skin problems, such as scarring and psoriasis. St. John’s wort can be taken as a pill, powder, or extract. It can also be applied as an oil or made into a tea.

Dosages

300 milligrams 2 to 3 times daily

What Research Shows

Likely Effective

May Be Effective

  • Atopic eczema —may help manage symptoms B1
  • Cesarean section—may improve pain and scarring when applied as an ointment E1

May Not Be Effective

Unlikely to Be Effective

Not Enough Data to Assess

  • Obsessive compulsive disorder H1
  • Pregnancy I1

Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.

Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.

Safety Notes

It is likely safe for most adults to take St. John’s wort orally in small doses for a short time, but reactions affecting the skin, stomach, muscles, and nerves are possible. Large doses may not be safe. Not enough studies have been done to say whether it is safe to use on the skin or by mouth for a long period. Women who are pregnant or breastfeeding should not use St. John’s wort. K1-K3

Interactions

Talk to your doctor about any supplements or therapy you would like to use. St. John’s wort interacts with many over the counter and prescription medications and can interfere with treatment or make conditions worse such as:

  • People with cancer, diabetes, or HIV should talk to their doctors before taking St. John’s wort. It may interact with their medicines.
  • People taking migraine medication should talk to their doctor before taking St. John’s Wort. It may interact with the medicine.
  • St. John’s wort may be dangerous when taken with anesthetics. It may cause heart failure or coma.
  • People taking heart medication should talk to their doctor before taking St. John’s wort. It may interact with the medicine.

References

REFA
Anxiety

REFA1
Lakhan SE, Vieira KF. Nutritional and herbal supplements for anxiety and anxiety-related disorders: systematic review. Nutr J. 2010 Oct 7;9:42.

REFB
Atopic Eczema

REFB1
Thandar Y, Gray A, et al. Topical herbal medicines for atopic eczema: a systematic review of randomized controlled trials. Br J Dermatol. 2017 Feb;176(2):330-343.

REFC
Attention Deficit Hyperactivity Disorder

REFC1
Sarris J, Kean J, et al. Complementary medicines (herbal and nutritional products) in the treatment of Attention Deficit Hyperactivity Disorder (ADHD): a systematic review of the evidence. Complement Ther Med. 2011 Aug;19(4):216-227.

REFD
Burning Mouth Syndrome

REFD1
Liu YF, Kim Y, et al. Burning mouth syndrome: a systematic review of treatments. Oral Dis. 2018 Apr;24(3):325-334.

REFE
Cesarean Section

REFE1
Samadi S, Khadivzadeh T, et al. The effect of Hypericum perforatum on the wound healing and scar of cesarean. J Altern Complement Med. 2010;16(1):113-117.

REFF
Depression

REFF1
Nahas R, Sheikh O. Complementary and alternative medicine for the treatment of major depressive disorder. Can Fam Physician. 2011;57(6):659-663.

REFF2
Sarris J, Panossian A, et al. Herbal medicine for depression, anxiety and insomnia: a review of psychopharmacology and clinical evidence. Eur Neuropsychopharmacol. 2011 Dec;21(12):841-860.

REFF3
Purgato M, Papola D, et al. Paroxetine versus other anti-depressive agents for depression. Cochrane Database Syst Rev. 2014 Apr 3;(4):CD006531.

REFF4
Apaydin EA, Maher AR, et al. A systematic review of St. John’s wort for major depressive disorder. Syst Rev. 2016;5(1):148.

REFF5
Seifritz E, Hatzinger M, et al. Efficacy of Hypericum extract WS (®) 5570 compared with paroxetine in patients with moderate major depressive episodes-a subgroup analysis. Int J Psychiatry Clin Pract. 2016;20(3):126-132.

REFF6
Ng QX, Venkatanarayanan N, et al. Clinical use of Hypericum perforatum (St John’s wort) in depression: A meta-analysis. J Affect Disord. 2017;210:211-221.

REFF7
Asher GN, Gartlehner G, et al. Comparative Benefits and Harms of Complementary and Alternative Medicine Therapies for Initial Treatment of Major Depressive Disorder: Systematic Review and Meta-Analysis. J Altern Complement Med. 2017 Dec;23(12):907-919.

REFG
Menopause

REFG1
Laakmann E, Grajecki D, et al. Efficacy of Cimicifuga racemosa, Hypericum perforatum and Agnus castus in the treatment of climacteric complaints: a systematic review. Gynecol Endocrinol. 2012 Sep;28(9):703-709.

REFG2
Liu YR, Jiang YL, et al. Hypericum perforatum L. preparations for menopause: a meta-analysis of efficacy and safety. Climacteric. 2014;17(4):325-335.

REFH
Obsessive Compulsive Disorder

REFH1
Sarris J, Camfield D, et al. Complementary medicine, self-help, and lifestyle interventions for obsessive compulsive disorder (OCD) and the OCD spectrum: a systematic review. J Affect Disord. 2012 May;138(3):213-221.

REFI
Pregnancy

REFI1
Dante G, Pedrielli G, et al. Herb remedies during pregnancy: a systematic review of controlled clinical trials. J Matern Fetal Neonatal Med. 2013 Feb;26(3):306-312.

REFJ
Premenstrual Syndrome

REFJ1
Dante G, Facchinetti F. Herbal treatments for alleviating premenstrual symptoms: a systematic review. J Psychosom Obstet Gynaecol. 2011 Mar;32(1):42-51.

REFK
Safety

REFK1
Izzo AA. Interactions between herbs and conventional drugs: overview of the clinical data. Med Princ Pract. 2012;21(5):404-428.

REFK2
Tsai HH, Lin HW, et al. Evaluation of documented drug interactions and contraindications associated with herbs and dietary supplements: a systematic literature review. Int J Clin Pract. 2012 Nov;66(11):1056-1078.

REFK3
Asher GN, Corbett AH, et al. Common Herbal Dietary Supplement-Drug Interactions. Am Fam Physician. 2017 Jul 15;96(2):101-107.

REFL
Smoking Cessation

REFL1
Hughes JR, Stead LF, et al. Antidepressants for smoking cessation. Cochrane Database Syst Rev. 2014 Jan 8;(1):CD000031.

REFM
Tooth Pain

REFM1
Raak C, Büssing A, et al. A systematic review and meta-analysis on the use of Hypericum perforatum (St. John’s Wort) for pain conditions in dental practice. Homeopathy. 2012;101(4):204-210.

  • EBSCO NAT Review Board Eric Hurwitz, DC
  • 201907
  • 20200327