PDR for Herbal Medicines

722 /ST. JOHN'S WORT PDR FOR HERBAL MEDICINES

inhibitor and an 81% decrease of the extrapolated 8-hour

indinavir trough value. The authors concluded that a

reduction of this magnitude could lead to development of

drug resistance and treatment failure (Piscitelli, et al., 2000).

Clinicians are warned that St. John's Wort may significantly

affect plasma concentrations of any drug that is metabolized

by the cytochrome P450 system.

Ethinyloestradiol and desogestrel (combined oral contracep-

tive) — Breakthrough bleeding has occurred with concomi-

tant use of St. John's Wort (Bon, 1999).

Hypericin causes a reduction in barbiturate-induced sleeping

times (Ozturk, 1992).

Theophylline — The herb has decreased theophylline levels

on a patient stabilized on theophylline therapy (Nebel, 1999).

Co-administration of St. John's Wort extract (LI 160) with

digoxin resulted in a significant decrease in digoxin Grough,

AUC (0-24), and Cmax values compared to placebo. There-

fore, St. John's Wort may reduce efficacy of digoxin and

make a patient a nonresponder, whereas increased toxicity

may be anticipated after withdrawal of the herb (Andreas,

1999). ... -

St. John's Wort (600-900 mg/day) taken concomitantly with

sertraline (50-75 mg/day) after 2 to 4 days, resulted in a

presumed serotonin syndrome consisting of dizziness, nau-

sea, vomiting, headache, epigastric pain, anxiety, confusion,

and/or feelings of restlessness and irritability. Cyprohepta-

dine was used to reverse the symptoms and after discontinua-

tion of the herb-drug therapy, all symptoms resolved (Lantz,

1999).

Nefazadine (100 mg BID) and St. John's Wort (300 mg TID)

taken simutaneously resulted in nausea, vomiting and

restlessness after 3 days of therapy. The symptoms improved

after stopping the nefazadine and continuing with St. John's

Wort (Lantz, 1999).

DOSAGE

Mode of Administration: Comminuted drug, herb powder,

liquid and solid preparations for internal use; liquid and

semi-solid preparations for external use; preparations made

with fatty oils for external and internal use.

How Supplied:

Capsules—(standardized at 0.3% hypericin) 125mg, 150mg,

250mg, 300mg, 350mg, 370mg, 375mg, 400mg, 424mg,

434mg, 450mg, 500mg, 510mg

Capsules, Extended Release—(standardized at 0.3% hyperi-
cin) 450mg, 900mg, lOOOmg

Dried Herb

Extract—I.T

Injection—1%

Liquid—300 mg/5ml, 250 mg/ml

Liquid Dilutions—3x, 6x, 30x,12c, 30c

Pellets—3x, 6x, 12x, 12c, 30c

Tablets—(standardized at 0.3% hypericin) lOOmg, 150mg,

300mg, 450mg

Tincture—1:10

Transdermal—900mg/24hr ' :-

Preparation: To prepare an infusion, use 2 teaspoonfuls of

drug in 150 ml boiling water and steep for 10 minutes.

Daily Dosage: In general, a range of 200 to 1000 micro-

grams/day of hypericin is recommended for treatment of

depression (Anon, 1996). Total hypericin concentrations of

Hypericum extracts may vary widely, therefore caution

should be taken in determining dosage (Fachinfo Helarium

Hypericum, 1996; Fachinfo Remotiv, 1996; Hansgen, 1993;

-Schmidt & Sommer, 1993; Vorbach, 1994; Woelk, 1994). -

For depressive moods, it is recommended the herb be

administered for the duration of 4 to 6 weeks; if no

improvement is apparent, a different therapy should be

initiated.

Depression:

Capsules/tablets — 300 mg of the standardized extract

should be administered three times daily (Clausson &

Muller, 1997; Fachinfo Helarium Hypericum, 1996).

Dried herb — 2 to 4 grams taken 3 times daily (Fachinfo

Helarium Hypericum, 1996; Fachinfo Remotiv, 1996; Hans-

gen, 1993; Schmidt & Sommer, 1993; Vorbach, 1994;

Woelk, 1994).

Tea — St. John's Wort as a tea is the traditional method of

administration, with a single dose of 2-3 grams dried herb

placed in boiling water. If dried herb of 2 grams is used, and

the dried herb to extract ratio is 6, a usual dose of the extract .-

would be 300 milligrams (Schultz, 1997).

Liquid extract 1:1 in 25% ethanol — 2 to 4 milliliters taken 3

times daily (Fachinfo Helarium Hypericum, 1996; Fachinfo *

Remotiv, 1996; Haensgen, 1993; Schmidt & Sommer, 1993;

Vorbach, 1994; Woelk, 1994).

Tincture: (1:10) in 45% ethanol — 2 to 4 milliliters, 3 times

a day (Fachinfo Helarium Hypericum, 1996; Fachinfo

Remotiv, 1996; Hansgen, 1993; Schmidt & Sommer, 1993;

Vorbach, 1994; Woelk, 1994).