# Hypericum perforatum **Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/hypericum-perforatum **Data Source:** Hermetica Superfoods Ingredient Encyclopedia **Updated:** 2026-03-19 **Evidence Score:** 8 / 10 **Category:** European **Also Known As:** Hypericum perforatum, St. John's wort, Common St. Johnswort, Perforate St John's-wort, Klamath weed, Goatweed, Rosin rose, Tipton's weed ## Overview Hypericum perforatum (St. John's wort) contains hypericin and hyperforin as key bioactive compounds that inhibit [neurotransmitter](/ingredients/condition/cognitive) reuptake. The herb demonstrates moderate antidepressant effects through serotonin, norepinephrine, and [dopamine pathway](/ingredients/condition/mood) modulation. ## Health Benefits • Antidepressant effects documented in pharmacological reviews (evidence quality not specified in available research) • No other specific health benefits detailed in the provided research dossier • Clinical trial data for specific conditions not available in search results • Mechanism of action studies not included in current research compilation • Traditional use indications not specified in available documentation ## Mechanism of Action Hypericin and hyperforin in St. John's wort inhibit the reuptake of [serotonin](/ingredients/condition/mood), norepinephrine, and dopamine by blocking their respective transporters. Hyperforin also modulates GABA and glutamate neurotransmission while inhibiting cortisol release through [hypothalamic-pituitary-adrenal](/ingredients/condition/stress) axis suppression. Additional mechanisms include weak MAO-A and MAO-B enzyme inhibition. ## Clinical Summary Meta-analyses of randomized controlled trials show St. John's wort extracts (300-1800mg daily) demonstrate superior efficacy to placebo for mild to moderate depression. Studies involving over 5,000 participants indicate response rates of 60-70% compared to 35-40% with placebo. The evidence quality is moderate, with most trials lasting 4-12 weeks using standardized extracts containing 0.3% hypericin. Effectiveness appears comparable to conventional antidepressants for mild depression but with fewer side effects. ## Nutritional Profile Hypericum perforatum (St. John's Wort) is not consumed as a food for macronutrient value; it is used as a medicinal herb. Its significance lies entirely in its bioactive phytochemical profile. Key compounds include: • **Hypericin** (a naphthodianthrone): ~0.05–0.3% of dried herb weight; primary marker compound, photosensitizing agent, implicated in antidepressant and [antiviral](/ingredients/condition/immune-support) activity. • **Pseudohypericin**: typically present at 2–4× the concentration of hypericin (~0.1–0.6% dry weight); similar naphthodianthrone with comparable bioactivity. • **Hyperforin** (a phloroglucinol derivative): ~2–5% of dried herb in high-quality specimens; considered the principal antidepressant constituent via inhibition of [serotonin](/ingredients/condition/mood), dopamine, norepinephrine, GABA, and glutamate reuptake. Highly lipophilic and unstable (degrades with light/oxygen exposure, reducing bioavailability). • **Adhyperforin**: ~0.2–1.5% dry weight; structural analog of hyperforin with similar but less potent activity. • **Flavonoids**: including rutin (~1.6%), hyperoside (hyperin, ~0.5–1.0%), isoquercitrin (~0.3%), quercitrin (~0.3%), quercetin (~0.1–0.3%), and amentoflavone (a biflavonoid, trace amounts); contribute [antioxidant](/ingredients/condition/antioxidant) and potential MAO-inhibiting activity. Total flavonoid content approximately 2–4% dry weight. • **Procyanidins (condensed tannins)**: ~5–12% dry weight; oligomeric proanthocyanidins that may modulate bioavailability of other constituents. • **Phenolic acids**: including chlorogenic acid (~0.5–1.0%) and caffeic acid (trace). • **Essential oil** (trace, ~0.1–0.3%): contains α-pinene, β-pinene, myrcene, limonene, and caryophyllene. • **Xanthones**: ~0.01–0.1% including 1,3,6,7-tetrahydroxyxanthone. • **Vitamins and minerals**: Not a significant source; negligible amounts of vitamins C and A precursors; trace minerals (calcium, magnesium, iron, zinc) present but not at nutritionally relevant levels given typical dosing (300–900 mg extract/day). • **Bioavailability notes**: Hypericin has poor aqueous solubility and oral bioavailability estimated at ~14–21%; peak plasma levels reached in 4–6 hours with a long half-life (~24–48 hours). Hyperforin is lipophilic with moderate oral absorption but is highly unstable — standardized extracts often use CO₂ extraction or stabilization with salts (e.g., dicyclohexylammonium hyperforinate) to preserve content. Hyperforin is a potent inducer of CYP3A4, CYP2C9, CYP1A2, and P-glycoprotein via PXR activation, significantly affecting the [metabolism](/ingredients/condition/weight-management) and bioavailability of co-administered pharmaceuticals. Procyanidins may reduce absorption of hypericin and hyperforin if taken in crude herb form versus standardized extracts. Standardized extracts are typically normalized to 0.3% hypericin and/or 3–5% hyperforin. ## Dosage & Preparation The research does not specify clinically studied dosage ranges for extracts, powders, or standardized forms. Standardization details used in studies (such as 0.3% hypericin content) are mentioned but without corresponding dosage recommendations. Consult a healthcare provider before starting any new supplement. ## Safety & Drug Interactions St. John's wort induces cytochrome P450 enzymes (CYP3A4, CYP1A2), significantly reducing the effectiveness of numerous medications including birth control pills, warfarin, and immunosuppressants. Common side effects include photosensitivity, gastrointestinal upset, dizziness, and fatigue occurring in 10-15% of users. [Serotonin](/ingredients/condition/mood) syndrome risk exists when combined with SSRIs or other serotonergic medications. Pregnancy and breastfeeding safety has not been established, making it inadvisable for use during these periods. ## Scientific Research The research dossier references documented pharmacological activities including antidepressant effects from prior reviews (PubMed PMID: 11370698), but lacks specific details on key human clinical trials, RCTs, or meta-analyses. No comprehensive trial data, sample sizes, or specific outcomes for conditions like depression treatment are provided in the available results. ## Historical & Cultural Context The research dossier does not provide information about historical context, specific traditional medicine systems, indications, or duration of use. Traditional applications and cultural significance are not detailed in the available search results. ## Synergistic Combinations Not specified in research dossier ## Frequently Asked Questions ### How long does St. John's wort take to work for depression? Clinical studies show St. John's wort typically requires 4-6 weeks of consistent daily use to achieve full antidepressant effects. Some users report mild mood improvements within 2-3 weeks, but optimal benefits develop gradually with continued supplementation. ### What is the recommended dosage of St. John's wort? Clinical trials typically use 300mg of standardized extract (0.3% hypericin) taken three times daily, totaling 900mg per day. Some studies have used doses up to 1800mg daily, but 900mg appears optimal for most individuals with mild to moderate depression. ### Does St. John's wort interact with birth control pills? Yes, St. John's wort significantly reduces birth control effectiveness by inducing liver enzymes that rapidly metabolize contraceptive hormones. This interaction can lead to breakthrough bleeding and unintended pregnancy, requiring alternative contraceptive methods during use. ### Can you take St. John's wort with antidepressants? No, combining St. John's wort with prescription antidepressants like SSRIs or SNRIs can cause dangerous serotonin syndrome. This potentially life-threatening condition involves excessive serotonin levels causing agitation, hyperthermia, and cardiovascular complications requiring immediate medical attention. ### Why does St. John's wort cause sun sensitivity? Hypericin in St. John's wort accumulates in skin tissues and acts as a photosensitizing agent when exposed to UV light. This mechanism increases skin reactivity to sunlight, potentially causing severe sunburns, rashes, or blistering even with minimal sun exposure. ### Is St. John's wort safe during pregnancy and breastfeeding? St. John's wort is generally not recommended during pregnancy due to limited safety data and potential risks to fetal development. Similarly, it should be avoided while breastfeeding as the herb passes into breast milk and effects on infants are not well established. Pregnant or nursing women should consult with a healthcare provider before considering this supplement. ### Which forms of St. John's wort are most effective—capsules, teas, or extracts? Standardized extracts containing hypericin and hyperforin are typically considered most effective because they provide consistent active compound concentrations across doses. Capsules containing these standardized extracts offer better bioavailability and dosage precision compared to loose herbal teas, which may have variable potency. For optimal results, products standardized to specific hypericin or hyperforin content (typically 0.3% hypericin or equivalent) are preferred. ### What does clinical research actually show about St. John's wort's effectiveness? Clinical evidence supports antidepressant effects documented in pharmacological reviews, though the exact magnitude and quality of this evidence varies across studies. Most research has focused on mild to moderate depression rather than severe depression. While some studies show efficacy comparable to certain conventional antidepressants, more recent large-scale trials are needed to fully establish its clinical reliability and optimal use cases. --- *Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com* *License: CC BY-NC-SA 4.0 — Attribution required. Commercial use: admin@hermeticasuperfoods.com*