Plant Profile

Perforate St John’s-wort

Compiled by the Omnia Sana editorial team from the plant database ·Last updated August 15, 2026
Hypericum perforatum
Family: Hypericaceae  ·  Parts used: Flower, Leaf  ·  Also known as: St John's wort, common St John's wort, perforate St John's wort

Common names in 32 European languages →

The complete database record: 3 documented constituents, 6 pharmacological actions, 10 traditional / indicated uses, with 31 cited sources.

Botanical Description

Erect, branching perennial herb with paired, oval leaves dotted with tiny translucent oil glands that look like pinpricks when held to the light (giving the species name 'perforatum'). Bright yellow, five-petalled flowers with numerous stamens and black dots along the petal edges are borne in flat-topped clusters, and release a reddish pigment when crushed.[4]

Height: 30-90 cm
Habit: Erect, branching perennial herb
Leaves: Paired, oval, dotted with tiny translucent oil glands
Flowers: Bright yellow, five-petalled, with numerous stamens and black-dotted petal edges, in flat-topped clusters
Stem: Erect, branching, with two raised longitudinal ridges
Root: Woody rootstock with spreading rhizomes
Fruit: Small, three-valved capsule
Flowering Period: June-September (traditionally around St John's Day, 24 June)

Habitat & Distribution

Grows in grassland, roadsides, woodland clearings and waste ground on well-drained soils; native to Europe, Western Asia and North Africa and widely naturalised elsewhere, including North America and Australia.[4]

Harvesting

The flowering tops (flower and upper leaf) are cut in summer as the flowers open, around the traditional St John's Day period, and dried quickly in a warm, shaded, airy place to preserve the hypericin and hyperforin content.[4]

Parts: Flower, Leaf
Season: Summer, at flowering

Key Constituents

Naphthodianthrones (hypericin, pseudohypericin)[4]

Red pigments historically used to standardise extracts; contribute to antiviral activity and are the compounds responsible for photosensitivity risk.

Phloroglucinols (hyperforin)[4]

Considered the principal compound behind the antidepressant activity and the main driver of the herb's potent CYP3A4/P-glycoprotein induction and drug-interaction profile.

Hyperforin
Flavonoids (hyperoside, quercetin, rutin)[4]

Antioxidant flavonoids contributing to overall activity.

FlavonoidsQuercetinRutin

Pharmacological Actions

Anti-inflammatory[5, 16, 17]
Antioxidant[6, 16, 17]
Antiviral[16, 17]
Emollient / skin-soothing[16, 17]
Sedative / sleep support[1, 2, 4, 5, 9, 11, 12, 13, 14, 16, 17]
Vulnerary (wound healing)[4, 16, 17]

Traditional & Indicated Uses

Arthritis / joint pain[17]Preliminary · 1/10

inferred from anti-inflammatory action

Mechanistic Exclude Ids: REF-0154, REF-1790
Evidence: 1
Label: Arthritis / joint pain

more plants for arthritis / joint pain →detailed sources →

Bruising[17]Preliminary · 1/10

inferred from vulnerary action

Mechanistic Exclude Ids: REF-0154
Evidence: 1
Label: Bruising

more plants for bruising →detailed sources →

Cold & flu[17]Preliminary · 1/10

inferred from antiviral action

Mechanistic Exclude Ids: REF-0154
Evidence: 1
Label: Cold & flu

more plants for cold & flu →detailed sources →

Eczema[17]Preliminary · 1/10

inferred from emollient action

Mechanistic Exclude Ids: REF-0154
Evidence: 1
Label: Eczema

more plants for eczema →detailed sources →

Infection (general)[17]Preliminary · 1/10

inferred from antiviral action

Mechanistic Exclude Ids: REF-0154
Evidence: 1
Label: Infection (general)

more plants for infection (general) →detailed sources →

Inflammation (general)[17]Preliminary · 1/10

inferred from anti-inflammatory action

Mechanistic Exclude Ids: REF-0154
Evidence: 1
Label: Inflammation (general)

more plants for inflammation (general) →detailed sources →

Insomnia / sleeplessness[17]Preliminary · 1/10

inferred from sedative action

Mechanistic Exclude Ids: REF-0154, REF-0842, REF-0843, REF-1790, REF-1794, REF-1796, REF-1797, REF-1798, REF-1799
Evidence: 1
Label: Insomnia / sleeplessness

more plants for insomnia / sleeplessness →detailed sources →

Skin irritation[17]Preliminary · 1/10

inferred from anti-inflammatory action

Mechanistic Exclude Ids: REF-0154, REF-1790
Evidence: 1
Label: Skin irritation

more plants for skin irritation →detailed sources →

Wounds[17]Preliminary · 1/10

inferred from vulnerary action

Mechanistic Exclude Ids: REF-0154
Evidence: 1
Label: Wounds

more plants for wounds →detailed sources →

Low mood / depression[1, 12, 13, 16]Strong · 9/10

Cochrane review and meta-analysis: hypericum extracts are superior to placebo and comparable to standard antidepressants (including SSRIs) in mild-to-moderate major depression, with fewer side effects. Evidence for severe depression is lacking.

Evidence: 9
Label: Low mood / depression

more plants for low mood / depression →detailed sources →

Traditional Use & History

St John's wort has a centuries-long European folk reputation as a wound-healing and nerve tonic herb, traditionally used for mild wounds, burns and nerve pain and to lift low mood; this traditional mood-supporting use is now one of the most extensively clinically studied applications of any herbal medicine, with standardised extracts shown comparable to conventional antidepressants for mild-to-moderate depression.[1, 4]

Preparations

Standardised extract[1]

Flowering-top extract standardised to hypericin and/or hyperforin content, taken as tablets or capsules; the best-studied clinical form for mood support.

Dosage

Standardised extract[1]

Clinical trials for mild-to-moderate depression commonly use around 300 mg of standardised extract three times daily (900 mg/day total); given extensive drug interactions, use should be discussed with a healthcare provider, especially alongside other medicines. Educational reference only, not a prescription.

Safety, Cautions & Contraindications

Safety note[16, 17]Caution

Significant drug interactions: strongly induces CYP3A4 and P-glycoprotein, reducing plasma levels of many drugs including oral contraceptives, antiretrovirals, cyclosporine, warfarin, and digoxin. May cause photosensitivity (fair-skinned individuals). Do not combine with SSRIs, SNRIs, or MAOIs (serotonin syndrome risk). Avoid in bipolar disorder.

Safety note[16, 17, 18]Caution

Duke (2002) rates St. John's wort as ++ (raised from earlier editions) and notes antidepressant, antiviral, antibacterial, and wound-healing activities at experimental and clinical levels. Hypericin and hyperforin are identified as key active constituents. Clinical evidence (score 2) confirms antidepressant efficacy in mild-to-moderate depression, and WHO/Commission E provide approval for this indication. Dose: 300 mg standardized extract (0.3% hypericin, 3–5% hyperforin) three times daily. Duke emphasizes the critical drug interaction: St. John's wort is a potent CYP3A4 inducer and can significantly reduce blood levels of many medications including oral contraceptives, cyclosporine, antiretrovirals, and warfarin. Avoid combined use with SSRIs (serotonin syndrome risk) and pharmaceutical antidepressants (Duke, 2002).

Herb-Drug Interactions

Antidepressants Serotonergic[19, 20, 21, 22]Avoid
Mechanism: St John's wort raises serotonin activity; combined with SSRIs, SNRIs or MAOIs it can trigger serotonin syndrome (agitation, tremor, sweating, rapid heartbeat). Reviews of clinical reports document serotonin syndrome and lethargy when it is combined with serotonin-reuptake inhibitors.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Antiretrovirals[19, 20, 23]Avoid
Mechanism: Potent CYP3A4 and P-glycoprotein induction lowers antiretroviral levels (indinavir exposure fell ~57%), risking loss of viral control and drug resistance.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Immunosuppressants[19, 20, 24]Avoid
Mechanism: Enzyme and transporter induction reduces ciclosporin and tacrolimus levels; reported to cause subtherapeutic concentrations and transplant rejection.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Hormonal Therapies[19, 25, 26]Avoid
Mechanism: Increased metabolism of ethinylestradiol and progestins reduces contraceptive exposure, causing breakthrough bleeding, ovulation and unplanned pregnancy. Randomised and controlled trials in women confirmed more breakthrough bleeding, reduced progestin levels and evidence of ovulation when St John's wort was added to the pill.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Anticoagulants Antiplatelets[19, 20, 22]Caution
Mechanism: CYP induction increases warfarin clearance and can lower INR, reducing the anticoagulant effect; close monitoring is needed.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Cardiac Glycosides[19, 27]Caution
Mechanism: P-glycoprotein induction lowers digoxin levels (AUC fell ~25% over ten days), which may reduce its effect.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Statins[19, 20, 22]Caution
Mechanism: CYP3A4 induction lowers levels of simvastatin and atorvastatin, potentially weakening their cholesterol-lowering effect.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Cyp3a4 Substrates[19, 20, 22]Caution
Mechanism: As a broad CYP3A4 and P-glycoprotein inducer, St John's wort can lower levels of many medicines cleared by this pathway; check each medication individually.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Chemotherapy Agents[21, 28, 29]Avoid
Mechanism: St John's wort strongly induces CYP3A4 and P-glycoprotein, speeding the breakdown and removal of several cancer medicines. In patients it cut the active form of irinotecan (SN-38) by about 42% and reduced imatinib exposure by roughly a third - enough to weaken treatment and risk drug resistance. Do not take St John's wort during chemotherapy.
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03

Herb-Herb Pairings

Saffron[30]

St John's wort raises serotonin activity and can cause serotonin syndrome when combined with other serotonin-boosting agents; pairing it with another mood-active, serotonergic herb such as saffron may add to this risk.

Type: caution
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Rhodiola Rosea[30]

St John's wort is a strong enzyme inducer and increases serotonin activity; combining it with another antidepressant-type herb such as rhodiola may add to serotonergic effects and unpredictably change how each is handled by the body.

Type: caution
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Valerian[30, 31]

St John's wort speeds up the breakdown of many substances and also raises serotonin activity; pairing it with a sedative herb such as valerian may add to drowsiness and can unpredictably change how each is handled by the body.

Type: caution
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03
Kava[30, 31]

St John's wort is a strong enzyme inducer and kava is a liver-metabolised sedative; combining them may add to central-nervous-system effects and alter how kava is processed, so combined use warrants caution.

Type: caution
Reviewed By: Omnia Sana (owner-authorized)
Reviewed Date: 2026-07-03

Harvest Readiness

[15]

Part: flower
Signals: Cut the flowering tops in mid-summer, when the flowers are in full bloom.
Basis: traditional
Source Quote: The flowering tops are harvested in mid-summer when the flowers are in full bloom.
Species Confirmed: 1
Notes: PFAF (REF-3274); the flowering tops are cut at full bloom in mid-summer (in flower May-August). Single lineage -> provisional.

[15]

Part: leaf
Signals: Gather the leaves with the flowering tops in mid-summer, at full bloom.
Basis: traditional
Source Quote: The flowering tops are harvested in mid-summer when the flowers are in full bloom.
Species Confirmed: 1
Notes: PFAF (REF-3274); the leaf is gathered with the flowering tops at full bloom. Single lineage -> provisional.

External Identifiers

GBIF ›Plants of the World Online ›Wikidata ›

References & Sources

  1. Ng, Q.X., Venkatanarayanan, N. and Ho, C.Y.X (2017) 'Clinical use of Hypericum perforatum (St John's wort) in depression: A meta-analysis', Journal of Affective Disorders, 210, pp. 211-221. doi:10.1016/j.jad.2016.12.048 Meta-analysis / review
    https://doi.org/10.1016/j.jad.2016.12.048
  2. Kholghi, G., Arjmandi-Rad, S., Zarrindast, M.R. and Vaseghi, S (2022) 'St. John's wort (Hypericum perforatum) and depression: what happens to the neurotransmitter systems?', Naunyn-Schmiedeberg's Archives of Pharmacology, 395(6), pp. 629-642. doi:10.1007/s00210-022-02229-z Traditional / reference
    https://doi.org/10.1007/s00210-022-02229-z
  3. Fugh-Berman, A (2000) 'Herb-drug interactions', Lancet, 355(9198), pp. 134-138. doi:10.1016/S0140-6736(99)06457-0 Traditional / reference
    https://doi.org/10.1016/S0140-6736(99)06457-0
  4. Nobakht, S.Z., Akaberi, M., Mohammadpour, A.H., Tafazoli Moghadam, A. and Emami, S.A (2022) 'Hypericum perforatum: Traditional uses, clinical trials, and drug interactions', Iranian Journal of Basic Medical Sciences, 25(9), pp. 1045-1058. doi:10.22038/IJBMS.2022.65112.14338 Meta-analysis / review
    https://doi.org/10.22038/IJBMS.2022.65112.14338
  5. Jiang, Z., Wang, F., Zhao, Y., Lu, L., Jiang, X., Huang, T., Lin, Y., Guo, L., Weng, Z. and Liu, E (2024) 'Hypericum perforatum L. attenuates depression by regulating Akkermansia muciniphila, tryptophan metabolism and NFkB-NLRP2-Caspase1-IL1beta pathway', Phytomedicine, 132, pp. 155847. doi:10.1016/j.phymed.2024.155847 Preclinical
    https://doi.org/10.1016/j.phymed.2024.155847
  6. Oliveira, A.I., Pinho, C., Sarmento, B. and Dias, A.C.P (2016) 'Neuroprotective Activity of Hypericum perforatum and Its Major Components', Frontiers in Plant Science, 7, pp. 1004. doi:10.3389/fpls.2016.01004 Meta-analysis / review
    https://doi.org/10.3389/fpls.2016.01004
  7. Russo, E., Scicchitano, F., Whalley, B.J., Mazzitello, C., Ciriaco, M., Esposito, S., Patane, M., Upton, R., Pugliese, M., Chimirri, S., Mammi, M., Palleria, C. and De Sarro, G (2013) 'Hypericum perforatum: pharmacokinetic, mechanism of action, tolerability, and clinical drug-drug interactions', Phytotherapy Research, 28(5), pp. 643-655. doi:10.1002/ptr.5050 Meta-analysis / review
    https://doi.org/10.1002/ptr.5050
  8. Saddiqe, Z., Naeem, I. and Maimoona, A (2010) 'A review of the antibacterial activity of Hypericum perforatum L', Journal of Ethnopharmacology, 131(3), pp. 511-521. doi:10.1016/j.jep.2010.07.034 Meta-analysis / review
    https://doi.org/10.1016/j.jep.2010.07.034
  9. Mennini, T. and Gobbi, M (2004) 'The antidepressant mechanism of Hypericum perforatum', Life Sciences, 75(9), pp. 1021-1027. doi:10.1016/j.lfs.2004.04.005 Meta-analysis / review
    https://doi.org/10.1016/j.lfs.2004.04.005
  10. Liu, Y., Jiang, Y., Huang, R., Yang, J., Xiao, B. and Dong, J (2013) 'Hypericum perforatum L. preparations for menopause: a meta-analysis of efficacy and safety', Climacteric, 17(4), pp. 325-335. doi:10.3109/13697137.2013.861814 Meta-analysis / review
    https://doi.org/10.3109/13697137.2013.861814
  11. Wurglics, M. and Schubert-Zsilavecz, M (2006) 'Hypericum perforatum: a 'modern' herbal antidepressant: pharmacokinetics of active ingredients', Clinical Pharmacokinetics, 45(5), pp. 449-468. doi:10.2165/00003088-200645050-00002 Meta-analysis / review
    https://doi.org/10.2165/00003088-200645050-00002
  12. Kasper, S (2001) 'Hypericum perforatum - a review of clinical studies', Pharmacopsychiatry, 34(Suppl 1), pp. S51-S55. doi:10.1055/s-2001-15467 Meta-analysis / review
    https://doi.org/10.1055/s-2001-15467
  13. Nathan, P (1999) 'The experimental and clinical pharmacology of St John's Wort (Hypericum perforatum L.)', Molecular Psychiatry, 4(4), pp. 333-338. doi:10.1038/sj.mp.4000557 Meta-analysis / review
    https://doi.org/10.1038/sj.mp.4000557
  14. Verotta, L (2003) 'Hypericum perforatum, a source of neuroactive lead structures', Current Topics in Medicinal Chemistry, 3(2), pp. 187-201. doi:10.2174/1568026033392589 Meta-analysis / review
    https://doi.org/10.2174/1568026033392589
  15. Plants For A Future 'Hypericum perforatum (St John's Wort)'. Available at: https://pfaf.org/user/Plant.aspx?LatinName=Hypericum+perforatum Traditional / reference
    https://pfaf.org/user/Plant.aspx?LatinName=Hypericum+perforatum
  16. Linde, K. and Berner, M.M. and Kriston, L (2008) 'St John's wort for major depression', Cochrane Database of Systematic Reviews, (4), pp. CD000448. doi:10.1002/14651858.CD000448.pub3 Meta-analysis / review
    https://doi.org/10.1002/14651858.CD000448.pub3
  17. Natural Standard (2013) 'Hypericum perforatum (St'. Traditional / reference
    https://scholar.google.com/scholar?q=Hypericum%20perforatum%20%28St
  18. Duke, J.A (2002) 'Handbook of Medicinal Herbs, Second Edition'. Traditional / reference
    https://scholar.google.com/scholar?q=Handbook%20of%20Medicinal%20Herbs%2C%20Second%20Edition
  19. Zhou, S., Chan, E., Pan, S.Q., Huang, M. and Lee, E.J.D (2004) 'Pharmacokinetic interactions of drugs with St John's wort', Journal of Psychopharmacology, 18(2), pp. 262-276. doi:10.1177/0269881104042632 Meta-analysis / review
    https://doi.org/10.1177/0269881104042632
  20. Izzo, A.A. and Ernst, E (2009) 'Interactions between herbal medicines and prescribed drugs: an updated systematic review', Drugs, 69(13), pp. 1777-1798. doi:10.2165/11317010-000000000-00000 Meta-analysis / review
    https://doi.org/10.2165/11317010-000000000-00000
  21. Borrelli, F. and Izzo, A.A (2009) 'Herb-drug interactions with St John's wort (Hypericum perforatum): an update on clinical observations', The AAPS Journal, 11(4), pp. 710-727. doi:10.1208/s12248-009-9146-8 Meta-analysis / review
    https://doi.org/10.1208/s12248-009-9146-8
  22. Nicolussi, S., Drewe, J., Butterweck, V. and Meyer zu Schwabedissen, H.E (2020) 'Clinical relevance of St. John's wort drug interactions revisited', British Journal of Pharmacology, 177(6), pp. 1212-1226. doi:10.1111/bph.14936 Meta-analysis / review
    https://doi.org/10.1111/bph.14936
  23. Piscitelli, S.C., Burstein, A.H., Chaitt, D., Alfaro, R.M. and Falloon, J (2000) 'Indinavir concentrations and St John's wort', Lancet, 355(9203), pp. 547-548. doi:10.1016/S0140-6736(99)05712-8 Clinical study
    https://doi.org/10.1016/S0140-6736(99)05712-8
  24. Barone, G.W., Gurley, B.J., Ketel, B.L., Lightfoot, M.L. and Abul-Ezz, S.R (2000) 'Drug interaction between St. John's wort and cyclosporine', Annals of Pharmacotherapy, 34(9), pp. 1013-1016. doi:10.1345/aph.10088 Clinical study
    https://doi.org/10.1345/aph.10088
  25. Murphy, P.A., Kern, S.E., Stanczyk, F.Z. and Westhoff, C.L (2005) 'Interaction of St. John's Wort with oral contraceptives: effects on the pharmacokinetics of norethindrone and ethinyl estradiol, ovarian activity and breakthrough bleeding', Contraception, 71(6), pp. 402-408. doi:10.1016/j.contraception.2004.11.004 Clinical study
    https://doi.org/10.1016/j.contraception.2004.11.004
  26. Pfrunder, A., Schiesser, M., Gerber, S., Haschke, M., Bitzer, J. and Drewe, J (2003) 'Interaction of St John's wort with low-dose oral contraceptive therapy: a randomized controlled trial', British Journal of Clinical Pharmacology, 56(6), pp. 683-690. doi:10.1046/j.1365-2125.2003.02005.x Randomized trial
    https://doi.org/10.1046/j.1365-2125.2003.02005.x
  27. Johne, A., Brockmoller, J., Bauer, S., Maurer, A., Langheinrich, M. and Roots, I (1999) 'Pharmacokinetic interaction of digoxin with an herbal extract from St John's wort (Hypericum perforatum)', Clinical Pharmacology and Therapeutics, 66(4), pp. 338-345. doi:10.1053/cp.1999.v66.a101944 Clinical study
    https://doi.org/10.1053/cp.1999.v66.a101944
  28. Mathijssen, R.H.J., Verweij, J., de Bruijn, P., Loos, W.J. and Sparreboom, A (2002) 'Effects of St. John's wort on irinotecan metabolism', Journal of the National Cancer Institute, 94(16), pp. 1247-1249. doi:10.1093/jnci/94.16.1247 Randomized trial
    https://doi.org/10.1093/jnci/94.16.1247
  29. Smith, P., Bullock, J.M., Booker, B.M., Haas, C.E., Berenson, C.S. and Jusko, W.J (2004) 'The influence of St. John's wort on the pharmacokinetics and protein binding of imatinib mesylate', Pharmacotherapy, 24(11), pp. 1508-1514. doi:10.1592/phco.24.16.1508.50958 Clinical study
    https://doi.org/10.1592/phco.24.16.1508.50958
  30. Izzo, A.A (2004) 'Drug interactions with St. John's Wort (Hypericum perforatum): a review of the clinical evidence', International Journal of Clinical Pharmacology and Therapeutics, 42(3), pp. 139-148. doi:10.5414/cpp42139 Meta-analysis / review
    https://doi.org/10.5414/cpp42139
  31. Caus, M.N., Lupoae, M. and Chitescu, C.L (2026) 'Efficacy and Safety of Herbal Supplements with Anxiolytic, Antidepressant, and Sedative Action: A Review of Clinical Data and Toxicological Risks', Pharmaceuticals, 19(3), pp. 399. doi:10.3390/ph19030399 Meta-analysis / review
    https://doi.org/10.3390/ph19030399

This fact sheet is generated automatically from the Omnia Sana plant database and reflects its latest synced data. It is provided for educational purposes only and is not medical advice. How this site is built.

Selected studies & references

ReviewEfficacy and Safety of Herbal Supplements with Anxiolytic, Antidepressant, and Sedative Action: A Review of Clinical Data and Toxicological Risks source↗ (2026)
ReviewHypericum perforatum: Traditional uses, clinical trials, and drug interactions source↗ (2022)
ReviewClinical relevance of St. John's wort drug interactions revisited source↗ (2020)
ReviewClinical use of Hypericum perforatum (St John's wort) in depression: A meta-analysis source↗ (2017)
ReviewNeuroprotective Activity of Hypericum perforatum and Its Major Components source↗ (2016)
ReviewHypericum perforatum L. preparations for menopause: a meta-analysis of efficacy and safety source↗ (2013)
ReviewHypericum perforatum: pharmacokinetic, mechanism of action, tolerability, and clinical drug-drug interactions source↗ (2013)
ReviewA review of the antibacterial activity of Hypericum perforatum L. source↗ (2010)

All 30 studies in the Knowledge Finder →

Educational use only. This profile summarises traditional and scientific sources for reference. It is not medical advice and not a substitute for a qualified practitioner. Some plants carry safety cautions and drug interactions - always check before use.
This profile is assembled automatically from the Omnia Sana plant database, which we curate by hand. How this site is built.

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