The dried fruit or berry of the chaste tree is often referred to as Monk’s pepper or chasteberry; it was historically thought to reduce libido or promote chastity. Chaste tree is also commonly referred to as vitex.
Uses and Benefits:
Standardized extracts of the chaste tree berry are popular in Europe, and now in North America, for a variety of women’s problems primarily related to the menstrual cycle. These disorders include menstrual cycle irregularities, the premenstrual syndrome (PMS), cyclic breast pain, dysfunctional uterine bleeding, and infertility. Historically, vitex has also been used for inflammatory conditions, diarrhea, flatulence, insufficient lactation, and menstruation induction.
Adverse Effects: Vitex appears to be very well tolerated. Reported side effects in the clinical studies are rare and transient (often similar in frequency to placebo), and primarily include mild gastrointestinal complaints, allergic reactions, or headaches. A single case of unexplained nocturnal seizures in a patient taking chaste tree berry, black cohosh, and evening primrose oil has been reported ; a cause-and-effect relationship with vitex is doubtful.
Side Effects and Interactions:
There are no reported interactions with vitex. Due to its potential effects on dopamine and prolactin, it is relatively contraindicated with other drugs that are dopamine antagonists (e.g., bromocriptine, metoclopramide, antiparkinson’s drugs).
Use during pregnancy and lactation should generally be avoided, although vitex has been employed to enhance fertility and stimulate lactation. In a case report of a woman undergoing unstimulated in vitro fertilization treatment, a combination herbal preparation containing vitex was associated with folliculogenesis and increased FSH, LH, and progesterone levels. In addition, the patient complained of symptoms suggestive of mild ovarian hyperstimulation syndrome.
Preparations & Doses:
Vitex preparations and doses vary considerably; only the standardized European products have been demonstrated to be effective. In the German clinical trials, small doses of standardized extract preparations are equivalent to about 30-40 mg of dried or crude herb, and are usually administered each morning. Agnolyte is marketed in the U.S. as Femaprin (Nature’s Way), and is usually given as one 4-mg tablet or 40 drops of extract per day. Herbalists in Britain and other English-speaking countries tend to use much larger doses of noncommercial preparations, equivalent to about 500-2000 mg/day of dried herb, often in liquid extracts and tinctures. A more recent European product is equivalent to about 120-240 mg of crude herb.