CHASTE TREE
Botanical name: Vitex agnus-castus
Synonyms: Vitex, Chasteberry, Monk’s pepper
MAJOR CHEMICAL CONSTITUENTS
The principal constituents are two labdane diterpenoids, including rotundifuran, vitexilactone, as well as vitexilactam A; flavonoids, including casticin, penduletin, chrysosplenol, isoorientin, and isovitexin; iridoids, including aucubin and agnuside; fatty oils, including caprinic acid, palmitic acid, and stearic acid as well as possibly linolenic acid; and essential oils.
TRADITIONAL AND HISTORICAL USES
Vitex agnus-castus is a deciduous shrub native to Mediterranean Europe and Central Asia. It has a long history of use for gynecologic complaints, as well as an alleged history of use as an aphrodisiac among monks (hence the common names monk’s pepper and chaste tree/berry). It is mentioned early in history by Greek philosopher and naturalist Plato (circa 428–348 bce), who described the herb’s aphrodisiac effects. The ability of chaste tree fruit to stimulate menstrual flow was reported by Lonicerus in 1582. It was mentioned in ancient herbals for the treatment of reproductive pain. For unknown reasons, chaste tree is not found in many Western herbals until the middle of the 1900s. Prior to that time it was not considered a primary herb in the US medical botany, Eclectic, or herbal literature. It is mentioned briefly by Felter and Lloyd in King’s American Dispensatory as a galactogogue, emmenagogue, and aphrodisiac.
CLINICAL INDICATIONS
Chaste tree is one of the most popular herbs in Europe, the United States, and other Western nations for the treatment of a number of gynecologic complaints. Its primary uses include the treatment of menstrual irregularities, especially secondary amenorrhea, oligomenorrhea, and dysmenorrhea; premenstrual symptoms and PMS; luteal phase dysfunction caused by luteal insufficiency, infertility (particularly secondary to endometriosis or anovulation), cyclic mastalgia, hyperprolactinemia, habitual miscarriage (attributed to progesterone insufficiency), insufficient lactation, and acne. Subclinical hyperprolactinemia has been suggested as a possible cause of endometriosis in some women, and is associated
with amenorrhea and other menstrual irregularities, and cyclic mastalgia. Chaste tree has been shown to increase progesterone levels and lengthen the hyperthermic phase of the basal metabolic temperature curve when taken daily for a minimum of three consecutive months.
MECHANISMS OF ACTION
The pharmacodynamics of chaste tree are not yet entirely understood. Dopaminergic activity, and consequently prolactin-lowering effects, have been demonstrated in preclinical studies and animal studies in vitro and in vivo, lending credence to the traditional uses of this herb in the treatment of menstrual irregularities; however, it appears contradictory to the herb’s use as a lactagogue (see Use in Pregnancy and Lactation). There is also evidence that suggests mediation of the herb’s effects via luteinizing hormone (LH), follicle-stimulating hormone (FSH), estrogen, and progesterone.
