Chaste tree is a large shrub (up to twenty-two feet tall) native to the Mediterranean and southern Europe. Although it flourishes on moist riverbanks, it is easily grown as an ornamental plant in American gardens, where its pretty blue-violet flowers blossom in midsummer. Today it is almost exclusively used for female problems.

The above seeming contradiction isn't the only one related to this herb. In history it has been used to inhibit excessive milk flow after birth, and to encourage it. It is used to treat post menopausal symptoms by some, and others say it exacerbates them. Some have used it to encourage conception, but others say that it does nothing for infertility.

The explanation for chaste berry's contradictory results is that it is an adaptogen. This means it helps the body adapt to changes by working through the adrenal glands (in this case the pituitary) to normalize hormone imbalance. In other words, it encourages hormonal deficiencies and constrains excesses. Other herbs that are adaptogens are taheebo, ginkgo, garlic, ginseng, echinacea, and goldenseal.

Because of its ability to balance the body, chaste tree berry reduces the production of certain hormones and increases the production of others. The reason it is used to treat infertility is that it tends to shift the balance in favor of the gestagens which hormones condition the body for pregnancy.

Chaste tree berry is especially effective in balancing the female reproductive system because it encourages the production of progesterone. This results in restoring menstruation, regulating heavy periods, and restoring fertility that resulted from hormonal imbalance. PMS tension, and the changes of menopause have also been decreased by this herb. Excess prolactin may be the cause of premenstrual breast tenderness and chaste tree berry will balance this hormone and thus relieve the problem.

Chaste tree berry is also used, in tincture form, to relieve pains in the limbs, to relief pain of paralysis, and to treat neuropathic muscular weakness. Some even use them to treat acne. The berries can be ground and used as a substitute for black pepper, the flowers and leaves, with their spicy aroma, used in flavoring.

Dose: Take 20 to 40 mg of the herb, or its equivalent daily. If using a tincture, 20 drops one or two times a day is normal. Capsules or tea (one cup) may also be used. Taking chaste berry shortly before bedtime may improve sleep. Chaste tree berry is slow acting and it may take two or three months to know if it is helping.

Warnings are in order but are not universally agreed upon. Some say pregnant women and nursing mothers should not take chaste tree berry. If a woman has a hormone-sensitive cancer (e.g. pituitary, breast, uterus, etc.) it might be best to avoid it. Chaste tree berry should be avoided if you are taking exogenous hormones such as menopausal hormone replacement therapies or oral contraceptives. Some rare adverse reactions include itchy allergic rash, mild nausea, or headaches. Some women have reported that the length of their cycle changed.