Safety and efficacy of St. John's wort (hypericum) during pregnancy and lactation.

BACKGROUND: There is a lack of basic knowledge on the part of both clinicians and patients as to the indications for use and safety of herbal medicines in pregnancy and lactation. This is one article in a series that systematically reviews the evidence for commonly used herbs during pregnancy and lactation. OBJECTIVES: To systematically review the literature for evidence on the use, safety, and pharmacology of St. John's wort focusing on issues …