St. John's Wort (Hypericum perforatum) (cont.)

Pharmacy Author:
Medical and Pharmacy Editor:

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

SIDE EFFECTS: The most common side effects associated with St. John's wort treatment are

  • asfunction.



STORAGE: Capsules and caplets should be stored at room temperature between 15 C and 30 C (59 F and 86 F).

PRESCRIBED FOR: St. John's wort is an over-the-counter (OTC) dietary supplement that is used for treatment of mild depression. It is also used to treat symptoms of mild anxiety and occasional episodes of sleep disturbances (insomnia), among others.

DOSING: Dietary supplements such as St. John's wort are not regulated by the FDA, and are not subject to rigorous clinical studies that evaluate standardized drug dosages. Read product labels and discuss dosing with your doctor before taking this dietary supplement.

The most common dosage that has been used in the majority of studies is 0.3% hypericin or 5% hyperforin in a dosage of 300 to 400 mg three times daily.

DRUG INTERACTIONS: St. John's wort increases activity of several liver enzymes. Consequently, St. John's wort may decrease blood levels of drugs that are metabolized or broken-down by these enzymes. Examples of such drugs are warfarin (Coumadin), fluconazole (Diflucan), voriconazole (Vfend), itraconazole (Sporanox), fentanyl (Sublimaze), digoxin (Lanoxin), birth control pills and many other drugs.

Medically Reviewed by a Doctor on 10/24/2014

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