Skip to main content
SupplementScience

Benefits of St. John's Wort

Reviewed by·PharmD, BCPS

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Evidence-Based Benefits

  • Mild-to-moderate depression treatment — The Cochrane Collaboration (Linde et al., 2008) analyzed 29 RCTs with 5,489 patients and concluded St. John's Wort extracts are superior to placebo and comparable to standard antidepressants for treating mild-to-moderate major depression, with significantly fewer adverse events leading to discontinuation
  • Comparable efficacy to SSRIs with better tolerability — Gastpar et al. (2006) conducted a 6-week double-blind RCT directly comparing 900mg/day St. John's Wort extract (STW 3-VI) to 20mg/day citalopram in 388 patients with moderate depression; both treatments were equally effective, but St. John's Wort had fewer side effects including less sexual dysfunction, nausea, and fatigue
  • Multi-target neurotransmitter modulation — Hyperforin, the primary active compound, inhibits reuptake of serotonin, norepinephrine, dopamine, GABA, and glutamate through activation of TRPC6 ion channels, providing broader neurotransmitter coverage than any single-mechanism SSRI; this may explain why some patients respond to SJW who failed SSRI monotherapy
  • Anxiety reduction — Kobak et al. (2005) demonstrated that St. John's Wort significantly reduced symptoms in patients with generalized social anxiety disorder, and multiple depression trials report anxiety symptom improvement as a secondary outcome
  • Seasonal affective disorder (SAD) support — Kasper (1997) reviewed evidence suggesting St. John's Wort's combined antidepressant and mild MAO-inhibiting properties make it particularly suited for winter depression, where serotonin and melatonin dysregulation play central roles

What the Research Says

St. John's Wort has one of the strongest evidence bases of any herbal medicine. The Cochrane Collaboration's landmark review (Linde et al., 2008) analyzed 29 RCTs with 5,489 patients and concluded that St. John's Wort extracts are superior to placebo and comparable to standard antidepressants for mild-to-moderate major depression, with significantly fewer side effects. Gastpar et al. (2006) directly compared 900mg/day St. John's Wort to 20mg citalopram in a double-blind RCT, finding equivalent efficacy with better tolerability. Mechanistically, hyperforin is the primary active compound, inhibiting reuptake of five neurotransmitters (serotonin, norepinephrine, dopamine, GABA, glutamate) through TRPC6 channel activation — a unique mechanism not shared by any pharmaceutical antidepressant. However, St. John's Wort is also one of the most potent known inducers of CYP3A4 and P-glycoprotein, the drug-metabolizing systems responsible for clearing approximately 50% of all prescription medications. This creates an extensive and dangerous interaction profile. Moore et al. (2000) documented the scope of these interactions in The Lancet, and subsequent case reports have confirmed life-threatening consequences including organ transplant rejection, HIV treatment failure, and unplanned pregnancies. The German Commission E and the European Medicines Agency both approve St. John's Wort for mild-to-moderate depression, but require drug interaction screening.

Related Conditions

DepressionAnxietyMoodSleepStress
Full St. John's Wort Guide

References

  1. Linde K, Berner MM, Kriston L (2008). St John's wort for major depression. Cochrane Database of Systematic Reviews. DOI PubMed
  2. Gastpar M, Singer A, Zeller K (2006). Comparative efficacy and safety of a once-daily dosage of hypericum extract STW3-VI and citalopram in patients with moderate depression: a double-blind, randomised, multicentre, placebo-controlled study. Pharmacopsychiatry. DOI PubMed
  3. Moore LB, Goodwin B, Jones SA, Wisely GB, Serabjit-Singh CJ, Willson TM, Collins JL, Kliewer SA (2000). St. John's wort induces hepatic drug metabolism through activation of the pregnane X receptor. Proceedings of the National Academy of Sciences. DOI PubMed
  4. Muller WE, Singer A, Wonnemann M, Hafner U, Rolli M, Schafer C (1998). Hyperforin represents the neurotransmitter reuptake inhibiting constituent of hypericum extract. Pharmacopsychiatry. DOI PubMed
  5. Kobak KA, Taylor LV, Bystritsky A, Kohlenberg CJ, Greist JH, Tucker P, Warner G, Futterer R, Vapnik T (2005). St John's wort versus placebo in social phobia: results from a placebo-controlled pilot study. Journal of Clinical Psychopharmacology. DOI PubMed
  6. Rahimi R, Nikfar S, Abdollahi M (2009). Efficacy and tolerability of Hypericum perforatum in major depressive disorder in comparison with selective serotonin reuptake inhibitors: a meta-analysis. Progress in Neuro-Psychopharmacology and Biological Psychiatry. DOI PubMed