St. John's wort (Hypericum perforatum) and breastfeeding: plasma and breast milk concentrations of hyperforin for 5 mothers and 2 infants.
BACKGROUND
Herbal preparations for depression, such as St. John's wort, are often preferred over pharmaceutical preparations by mothers and midwives after childbirth because these preparations are available to patients as over-the-counter "natural" treatments and are popularly assumed to be safe. The only existing report on St. John's wort excretion into human milk showed that only 1 active component (hyperforin) was detectable in breast milk, but was not detectable in the infants' plasma. Another report found more cases of minor problems in infants breast-fed by women taking St. John's wort. However, significance was reached only in comparison with disease-matched women (p<.01), not healthy controls (p=.20).


METHODS
Five mothers who were taking 300 mg of St. John's wort 3 times daily (LI 160 [Jarsin], Lichtwer Pharma GmbH; Berlin, Germany) and their breastfed infants were assessed. Thirty-six breast milk samples (foremilk and hindmilk collected during an 18-hour period) and 5 mothers' and 2 infants' plasma samples were analyzed for hyperforin levels by tandem mass spectrometry (LC/MS/MS; limit of quantification=0.1 ng/mL). Data were gathered from January 2001 to February 2002.


RESULTS
Hyperforin is excreted into breast milk at low levels. However, the compound was at the limit of quantification in the 2 infants' plasma samples (0.1 ng/mL). Milk/plasma ratios ranged from 0.04 to 0.13. The relative infant doses of 0.9% to 2.5% indicate that infant exposure to hyperforin through milk is comparable to levels reported in most studies assessing anti-depressants or neuroleptics. No side effects were seen in the mothers or infants.


CONCLUSIONS
These results add to the evidence of the relative safety of St. John's wort while breast-feeding found in previous observational studies.
Department of Child and Adolescent Neuropsychiatry, Medical University Vienna, Vienna, Austria, and the Division of Clinical Pharmacology and Toxicology, Hospital for Sick Children, Toronto, Ontario, Canada. claudia.klier@meduniwien.ac.at
Claudia M
CM
Klier
Brigitte
B
Schmid-Siegel
Miriam R
MR
Schäfer
Gerhard
G
Lenz
Alois
A
Saria
Amy
A
Lee
Gerald
G
Zernig
D000328:Adult; D001942:Breast Feeding / Q000009:adverse effects; D001643:Bridged Bicyclo Compounds / Q000493:pharmacokinetics / Q000627:therapeutic use; D003866:Depressive Disorder / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism; D005260:Female; D006801:Humans; D020902:Hypericum / Q000009:adverse effects / Q000378:metabolism*; D007223:Infant; D013058:Mass Spectrometry; D018811:Maternal Exposure / Q000009:adverse effects; D008431:Maternal-Fetal Exchange; D008895:Milk, Human / Q000737:chemistry* / Q000378:metabolism; D010696:Phloroglucinol / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000627:therapeutic use; D008517:Phytotherapy / Q000009:adverse effects / Q000379:methods*; D028321:Plant Preparations / Q000032:analysis / Q000097:blood / Q000493:pharmacokinetics*; D011247:Pregnancy; D013729:Terpenes / Q000493:pharmacokinetics* / Q000627:therapeutic use
D001643:Bridged Bicyclo Compounds; D028321:Plant Preparations; D013729:Terpenes; D010696:Phloroglucinol; C001654:hyperforin