St. John's Wort (Hypericum perforatum)

GENERIC NAME: Hypericum perforatum

BRAND NAME: St. John's Wort

DRUG CLASS AND MECHANISM: St. John's wort is a commonly used over-the-counter (OTC) dietary supplement that is used to treat mild depression, anxiety, and sleep disorders. St. John's wort is a plant that has bright yellow flowers. A number of compounds that have pharmacological activity including naphthodianthrones (hypericin, pseudohypericin, protohypericin, and cyclopseudohypericin), flavonoids (quercetin, rutin, and luteolin), hyperforin, several amino acidsand tannins have been isolated from St. John's wort.

The exact mechanism of how St. John's wort works to alleviate symptoms of depression is not understood. Hyperforin and hypericin are thought to be the major active components. Studies suggest that hyperforin affect serotonin, norepinephrine, and dopamine which are chemicals that affect mood. Other studies show that hypericum has weak effects on catechol-O-methyl transferase, an enzyme that is responsible for the breakdown of chemicals in the brain including serotonin, norepinephrine, and dopamine. Read product labels and discuss dosing with your doctor before taking this dietary supplement.

PRESCRIPTION: No

GENERIC AVAILABLE: Yes

PREPARATIONS: Capsules: 300 mg, Caplets: 300 mg are most common, but some preparations contain 325 mg.

Medically Reviewed by a Doctor on 10/24/2014



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