St John's Wort (Herb/Suppl)

Brand and Other Names:amber, amber touch & teal, more...balm-of-warrior's wound, balsana, demon chaser, devil's scourge, goatweed, hypericin, hypericum perforatum, Johanniskraut, klamath weed, millepertuis, rosin rose, tipton weed, walpurgiskraut, witcher's herb
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Suggested Dosing

Depression, Mild-moderate

Preparations vary greatly in chemical quality and content; may be standardized regarding quantity of hypericin (commonly 0.3%) or hyperforin (commonly 3% to 5%) constituents

Hypericin 0.3% standardized extract

  • 300 mg PO TID, OR
  • 1200 mg PO qDay

Hypericin 0.2% standardized extract: 250 mg PO BID

Hyperforin 5% standardized extract: 300 mg PO TID

Crude: 2-4 g PO qDay-TID

Obsessive-compulsive Disorder

Hypericin 0.3% standardized extract (XR): 450 mg PO BID

Premenstrual Syndrome

Hypericin 0.3% standardized extract: 300 mg PO qDay

Glioblastoma Multiforme (Orphan)

Orphan indication sponsor

  • Nexell Therapeutics, Inc; 2751 Centerville Rd., Suite 210; Wilmington, DE 19808

Cutaneous T-Cell Lymphoma (Orphan)

Orphan indication sponsor

  • Nexell Therapeutics, Inc; 2751 Centerville Rd., Suite 210; Wilmington, DE 19808

Other Information

No more than 8 weeks of use

Avoid abrupt discontinuation due to withdrawal


Suggested Uses

Oral: Depression (mild-moderate), psychosomatic disorder, obsessive-compulsive disorder, anxiety, premenstrual syndrome, burning mouth syndrome, neuropathy

Topical: atopic dermatitis, wound healing


Although controversy exists, available evidence suggests that for depression more effective than placebo and may be as effective as standard antidepressants with less side effects (Cochrane Review 2008)

However a JAMA report (2009) shows no improvement over placebo for severe depression, but then, sertraline didn't perform any better either for 2 of the primary outcomes

Increased rate of healing in 2nd and 3rd degree burns



Interaction Checker

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            Adverse Effects

            Frequency Not Defined




            Dry mouth


            GI discomfort





            Menstrual irregularities




            Skin rash




            Hypersensitivity to ingredients

            Coadministration with antineoplastics, anticoagulants, and anti-infectives (including antivirals), as well as cobicistat, boceprevir, voriconazole, and telaprevir

            Alzheimer disease, bipolar disorder, psychosis, schizophrenia, tyramine-containing foods


            Avoid strong sunlight

            Inducer of CYP3A4

            May reduce efficacy of oral contraceptives and concentrations of CYP3A4 substrate drugs

            Quality varies widely among commercial products; some contain very low quantities of hypericin

            Drug may cause serious interactions with other medications

            Worsening of dementia in people with Alzheimer disease suggested

            May precipitate psychotic episodes in patients with schizophrenia

            May precipitate mania symptoms in bipolar patients and may speed up the cycles between mania and depression

            May precipitate mania symptoms in patients with major depression

            May alter serotonin levels in the brain, may interfere with anesthesia, and may lead to serious heart complications during surgery; stop therapy two weeks prior to surgery


            Pregnancy & Lactation


            Not recommended; studies on effects in the developing fetus lacking


            Hypericin and hyperforin detected in breast milk; avoid during lactation until long-term studies show a lack of toxicity in breastfeeding infants

            Pregnancy Categories

            A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA: Information not available.



            Mechanism of Action

            A chemical in St. John's wort called hypericin has been suggested to have an effect on improving mood; more recently, information suggests other chemicals like hyperforin may play a larger role; the chemicals may act on messengers in the nervous system that regulate mood

            Reports have shown that hyperforin may have a high affinity for GABA, adenosine, and glutamate receptors, inhibit monoamine oxidase type A (MAO-A) and type B (MAO-B), and may inhibit norepinephrine, serotonin, and dopamine reuptake; downregulation of beta-adrenergic receptors also reported

            Topical: antibacterial, increased epithelialization


            Bioavailability: 15-20% (hypericin, pseudohypericin, hyperforin

            Peak serum time: 0.5-3 hr (pseudohypericin); 4.6-8.1 hr (hypericin); 2.8-3.6 hr (hyperforin)

            Steady-state levels: 4 days


            Protein-bound: Highly bound


            Half-life: 25 hr (hypericin); 9 hr (hyperforin)

            Medscape prescription drug monographs are based on FDA-approved labeling information, unless otherwise noted, combined with additional data derived from primary medical literature.