Vervain (Verbena officinalis) contains iridoid glycosides (e.g., verbenalin, hastatoside), verbascoside, and flavonoids. Vervain is a purported galactogogue;[1-3] however, no scientifically valid clinical trials support this use. Galactogogues should never replace evaluation and counseling on modifiable factors that affect milk production.[4,5] No data exist on the excretion of any components of vervain into breastmilk or on the safety and efficacy of vervain in nursing mothers or infants. Vervain is "generally recognized as safe" (GRAS) as a food by the U.S. Food and Drug Administration. It is well tolerated, but gastrointestinal and allergic reactions have been reported.
Dietary supplements do not require extensive pre-marketing approval from the U.S. Food and Drug Administration. Manufacturers are responsible to ensure the safety, but do not need to prove the safety and effectiveness of dietary supplements before they are marketed. Dietary supplements may contain multiple ingredients, and differences are often found between labeled and actual ingredients or their amounts. A manufacturer may contract with an independent organization to verify the quality of a product or its ingredients, but that does not certify the safety or effectiveness of a product. Because of the above issues, clinical testing results on one product may not be applicable to other products. More detailed information about dietary supplements is available elsewhere on the LactMed Web site.