St. John's wort

Scientific

Hypericum perforatum (family Hypericaceae) is a perennial herb reaching 30–80 cm, native to temperate Europe and western Asia. The plant produces small bright yellow five-petaled flowers in mid-summer; the leaves are characteristically dotted with translucent glands containing aromatic and pharmacologically-active compounds.

The principal active compounds:

• Hypericin — a red anthraquinone derivative; one of the bioactive compounds; also responsible for the red pigment that bleeds from crushed flowers (the “St. John’s blood” tradition)
• Hyperforin — a prenylated phloroglucinol derivative; the principal antidepressant compound; modulates serotonin, norepinephrine, dopamine, GABA, and glutamate transport
• Various flavonoids — quercetin, rutin, and others contributing to antioxidant activity

Cultural and historical

The species’ association with St. John the Baptist (feast day June 24, summer solstice) is one of the oldest documented Christian-into-folk traditions. Pre-Christian European traditions used the plant at midsummer for protection, healing, and divination; the Christian calendar absorbed and re-named the existing solstice flower.

The name “wort” is Old English for “plant” — St. John’s wort literally means “St. John’s plant.” The Latin Hypericum derives from Greek hyper + eikon (above-image), referring to ancient practice of hanging St. John’s wort above religious images to ward off evil spirits.

Traditional European folk uses across centuries:

• Hung in doorways and windows at midsummer for protection
• Used for wounds, burns, and bruises (the red-staining oil-infused preparations are still made today as topical applications)
• Used internally for melancholy, anxiety, nervous complaints

Modern phytomedicine and antidepressant use

St. John’s wort is among the most extensively studied herbal medicines of the modern era. Multiple randomized clinical trials and several major meta-analyses support efficacy for mild to moderate depression, with effects comparable to selective serotonin reuptake inhibitors (SSRIs) in some studies. The species is widely prescribed by physicians in Germany and Austria (where it outsells fluoxetine for some indications); FDA-approved as a dietary supplement (not as a drug) in the US.

The drug-interaction concerns are real and clinically significant:

• St. John’s wort induces cytochrome P450 enzymes (especially CYP3A4) — accelerating the metabolism of many drugs
• Reduced efficacy of: oral contraceptives, HIV protease inhibitors, certain cancer treatments, anticoagulants like warfarin, immunosuppressants, antidepressants of other classes
• Combined with serotonergic medications, can produce serotonin syndrome

For these reasons, patients on multiple medications must consult prescribers before starting St. John’s wort.

See also

Auto-generated from this entry’s typed relations: frontmatter, grouped by relation type so the editorial signal isn’t flattened.

• Shares approach with: [[bilberry]] · [[wild-bergamot]] · [[turkey-tail]] · [[sweet-woodruff]] · [[spelt]] · [[soursop]]
• Member of: [[plants]]

Sources

• Wikipedia — Hypericum perforatum

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A plant entry in the 0mn1.one [[directory]].