Chasteberry, also referred to as vitex, chaste tree and agnus castus, has a long history of use for addressing a variety of conditions triggered by female hormonal imbalances. Examples include breast tenderness, premenstrual syndrome and infertility. The University of Pittsburgh Medical Center, or UPMC, notes a "growing body of scientific research" that confirms the benefits of this herb. The treatment of most conditions calls for a standard dosage, but you should talk to to a doctor well-versed in alternative therapies about an appropriate dose for your needs and other aspects of proper use.
UPMC states a typical dosage of chasteberry consists of 20 mg of a dried supplement three times a day or 40 drops of a liquid extract taken in the morning. Ultimately, working with a knowledgeable health-care provider will help determine the best dosage for your needs.
The University of Michigan Health System reports the following daily doses used in studies for various conditions: female infertility and fibrocystic breast disease, 35 to 40 mg of dried extract or 40 drops of liquid extract; premenstrual syndrome, 20 mg; acne, amenorrhea, dysmenorrheal and menorrhagia, 40 drops of extract. Forty drops of extract equals about 40 mg of dried extract.
Length of Use
Often, you need to use chasteberry for at least several months before achieving any therapeutic benefit. Addressing hormonal imbalances takes time. For example, you might not see an improvement in PMS symptoms until taking the herb through three menstrual cycles. The University of Maryland Medical Center states you need to take chasteberry anywhere from one year to 18 months to address amenorrhea, or absence of menstruation. It notes one study in which women began to have periods again after six months of use. Working with a doctor knowledgeable about herbal medicine can make sure you use chasteberry properly and effectively.
Caution in Certain Individuals
Drugs.com notes the use of chasteberry is contraindicated if you have abnormal ovarian function or are pregnant or breast-feeding. While chasteberry might enhance fertility, it could interfere with actions of fertility drugs. If you are undergoing standard infertility treatments, talk to your doctor about the appropriateness of using chasteberry. The Memorial Sloan Kettering Cancer Center states this herb has demonstrated estrogenic activity, which could prove problematic if you suffer from breast cancer or other hormone-sensitive diseases.
Other Considerations for Use
Chasteberry might interfere with the effectiveness of hormonal birth control pills, drugs that affect the pituitary gland, levodopa, dopamine agonists and dopamine receptor antagonists. A long history of use in Germany suggests chasteberry does not carry a risk of significant adverse effects, but some side effects have been reported, including stomach upset, itching, rash, acne, menstrual irregularities, nausea and headache.