Vitex, or chaste tree, is the fruit of a shrub in the verbena family native to west Asia and southwestern Europe. It was introduced throughout Europe at an early date and is naturalized in much of the southeastern United States. The fruits are grown commercially in Europe.
Vitex has been used for menstrual difficulties for at least 2,500 years. Hippocrates (460-377 B.C.) wrote, "If blood flows from the womb, let the woman drink dark wine in which the leaves of the vitex have been steeped." Its use for gynecological conditions is also noted in the works of Pliny (A.D. 23-79): "The trees furnish medicines that promote urine and menstruation." In the late 1800s American physicians used a tincture of the fresh berries to increase milk secretion and treat menstrual disorders.
During the past forty years, research has focused on the use of vitex for premenstrual syndrome (PMS) and menstrual difficulties. The biological activity cannot be attributed to a single chemical ingredient, though flavonoids are major components.
Between 5 and 30 percent of women may be affected by PMS. A 1992 survey of German gynecologists evaluated the effect of a vitex preparation on 1,542 women diagnosed with PMS. Both physicians and patients assessed effectiveness, with 90 percent reporting relief of symptoms after treatment averaging 25.3 days.
In one clinical drug-monitoring study on the effectiveness and safety of long-term treatment with a vitex fruit tincture, 1,571 women with menstrual disorders and PMS were followed for a period of seven days to six years (average 147.6 days). In 90 percent of patients, the treatment eliminated or alleviated symptoms of PMS.
German health authorities allow vitex preparations for disorders of the menstrual cycle, pressure and swelling in the breasts, and PMS. In Germany, vitex preparations are frequently used in the safe and effective treatment of PMS, heavy or too frequent periods, acyclic bleeding, infertility, suppressed menses, and other conditions. Vitex is an excellent example of an herbal medicine which serves as a low-priced tool in European gynecological practice, rather than as an " alternative" to conventional treatment.
Most European clinical studies have been done on a proprietary extract (tincture) and capsules called Agnolyt. In the United States the dried fruit is available in whole or pulverized form, capsules, tinctures, tablets, and other preparations.
Do not use vitex if you are pregnant or receiving hormone replacement therapy. Rare side effects include early menstruation following delivery (resulting from activation of the pituitary), as well as rare cases of itching, rashes, and gastrointestinal symptoms. In clinical trials, side effects have been reported in fewer than 2 percent of patients.