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Herb Profile
St. John's Wort Hypericum Perforatum
Hypericum perforatum
St.
Last reviewed: •3 sources citedReport a correctionProfile-wide ·Unassigned
Use extra caution — Photosensitivity; GI symptoms; major drug interaction risk Details
- Evidence
- Editorial Grade Not Demonstrated By Recorded Studies
- Typical onset
- Varies by prep
- Safety rating
- Moderate caution
- Best for
- Mood Support, Antidepressant, Nervine, Stress
- Avoid / review if
- Pregnancy, Bipolar Disorder, Strong CYP3A4 Inducer
At a glance
From this profile's structured data- Evidence
- Editorial grade not demonstrated by recorded studies
- Safety
- Photosensitivity; GI symptoms; major drug interaction risk
- Profile context
- mood_support, antidepressant, nervine
Safety
Safety & Cautions
Photosensitivity; GI symptoms; major drug interaction risk
Elevated caution
Caution level: Elevated. One caution category applies — read it before use.
- Interaction-AwareMedication or interaction context is explicitly noted.
Detailed safety fields
Pregnancy, breastfeeding, and contraindications
- Pregnancy
- Bipolar Disorder
- Strong CYP3A4 Inducer
- Reduces Effectiveness Of Many Medications
Safety classifications
- Interaction-Aware: Medication or interaction context is explicitly noted.
Full safety note
- Photosensitivity; GI symptoms; major drug interaction risk
Safety labels
- Interaction-Aware
Evidence-based safety
Caution when combined
Severity and certainty are shown separately. A high-priority caution can still be theoretical: these pairings are screened from shared contraindication mechanisms and are not automatically documented clinical interactions. Provenance identifies the source fields that produced each flag; it does not upgrade the certainty of the pairwise claim.
High-Priority Caution
26 flagged pairingsSerotonergic activity
High-Priority Caution
26 flagged pairingsSerotonergic activity
Representative pairings are shown below. Large mechanism groups are intentionally summarized to keep profiles focused and crawl-efficient.
Serotonergic activityCertainty: Theoretical
Data provenance recorded for 26 of 26 pairings in this mechanism group.
- 5-HTP — Theoretical interaction certainty
- Caffeine — Theoretical interaction certainty
- crocetin — Theoretical interaction certainty
- crocin — Theoretical interaction certainty
- Crocus Sativus — Theoretical interaction certainty
- Damiana — Theoretical interaction certainty
- DMT — Theoretical interaction certainty
- Ginkgo — Theoretical interaction certainty
- Panax Red Ginseng — Theoretical interaction certainty
- Panax White Ginseng — Theoretical interaction certainty
- Harmaline — Theoretical interaction certainty
- Harmine — Theoretical interaction certainty
+14 more pairings share this mechanism. Use the Safety Checker to review a specific combination.
Evidence
Evidence Summary
Evidence lens
Treat this profile as unresolved until source review is complete.
Needs reviewEditorial Grade Not Demonstrated By Recorded Studies
Human clinical evidence: Not the primary signal
Mechanistic / preclinical: Mechanism mapped — Neurotransmitter Modulation · Stress Response Modulation
Research maturity: Theoretical / mechanistic research — Mechanistic or unresolved evidence is kept separate from established human outcomes.
Safety boundary: Safety note available — Photosensitivity; GI symptoms; major drug interaction risk
This profile cites 3 human studies.
Study design details
Evidence Grade
Evidence grade not assigned
Evaluation of methodological rigor, population reach, and evidence alignment.
- Design Match
- Narrative review
- Risk of Bias
- High
- Consistency
- Not assessed
Strongest recorded design is a narrative review, drawn from 3 recorded studies, none of which measured an outcome in people.
How evidence grades work
Each grade reflects the strength and consistency of published human evidence — not marketing claims. Grades are based on study count, design quality, effect size, consistency, and recency.
- Strong
- Multiple RCTs, consistent direction, adequate effect size
- Moderate
- Some RCTs or consistent observational data in humans
- Preliminary / Mixed
- Animal or in-vitro only, or conflicting human data
- Traditional / Theoretical
- Traditional use only; no controlled human trials
Clinical Study Summaries (3)0 human evidence sources · 0 human trials · Participant totals not consistently reported · Consistency not yet classifiable
What the evidence actually shows
This table contains 3 structured sources, including 0 human evidence sources; 0 are human trials.
| Study | Design | N | Dose | Duration | Population | Outcome | Result & magnitude | Source |
|---|---|---|---|---|---|---|---|---|
Fugh-Berman A et al. · Lancet · 2000 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
St. John's wort (Hypericum perforatum) and depression: what happens to the neurotransmitter systems? Kholghi G et al. · Naunyn Schmiedebergs Arch Pharmacol · 2022 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
PubMed indexed authors · 2006 Background | Narrative review Summarizes selected literature without the full prespecified search and selection methods of a systematic review. | — | — | — | — | — | — | PubMed → |
Dosing & Timing
- Dose guidance
- Standardized extract (0.3% hypericin or 2 5% hyperforin): ~900 mg/day in divided doses; formulation dependent
How St. John's Wort Hypericum Perforatum works
Simplified mechanism pathway based on preclinical and pharmacological evidence. Does not confirm clinical efficacy.
Mechanism Pathway — How St. John's Wort Hypericum Perforatum Works
CompoundTarget / ReceptorMechanismEffect / Outcome
Mechanisms & biological pathways (preclinical)
- Neurotransmitter Modulation
- Stress Response Modulation
Active Compounds
Key constituents studied in St. John's Wort Hypericum Perforatum, with full pharmacology and safety profiles.
- Hyperforin — active compound in St. John's Wort Hypericum Perforatum
- Hypericin — active compound in St. John's Wort Hypericum Perforatum
- Kaempferol — active compound in St. John's Wort Hypericum Perforatum
- Quercetin — active compound in St. John's Wort Hypericum Perforatum
- Rutin — active compound in St. John's Wort Hypericum Perforatum
Compare related active botanicals
Explore botanicals with similar chemistry, effects, or safety considerations in the Botanical Activity Atlas.
Compare & Sourcing
Compare side-by-side tradeoffs or verify active marker guidelines.
Sourcing options
St. John's Wort product picks
Recommendation status
Product recommendations are not shown for this profile because the current site safety and monetization policy does not permit them.
Product form & quality guidelines
When sourcing St. John's Wort Hypericum Perforatum, verify the label for:
- Standardized extract: Confirm active content percentages on the supplement facts panel (e.g. standardized to specific marker compounds) rather than simple raw herb weights.
- Third-party testing: Look for independent purity labels (USP, NSF, ConsumerLab, or Eurofins) to ensure the product is free from heavy metals, solvents, and contaminants.
- Form bioavailability: Ensure the form matches evidence-supported configurations (e.g. standardized active extracts like bacosides, withanolides, or curcuminoids) for optimal onset and digestion tolerance.
Safety first · Harm reduction
This information is educational and not medical advice. Start low, avoid risky combinations, and consult a licensed clinician before making health decisions—especially if you use medications, have diagnosed conditions, or are pregnant/breastfeeding.
Learn how we evaluate confidence, safety, and intensity on the methodology page.
Editorial Review
Checked against primary sources, cited evidence, and contraindication language before publication. Evidence claims, safety language, and affiliate modules are reviewed independently. Not personal medical advice.
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