Dong quai, also known as Angelica sinensis or danggui, is one of the most respected herbs in traditional Chinese medicine. Extensively used also in Korea and Japan, dong quai is considered the "female ginseng" and used extensively to treat a variety of gynecological complaints, from hot flashes to lack of sleep due to hormonal changes. While both men and women can obtain benefits from using dong quai, the herb has long has a reputation for regulating the menstrual cycle. It is prescribed by natural doctors to treat menopausal symptoms and hormonal changes, and to induce the relaxation of uterine muscles. Dong quai is often combined with black cohosh to treat PMS, and is sometimes prescribed to women suffering from endometriosis. Because of its intense effect on the reproductive system, dong quai is not recommended during pregnancy.

As a general medicinal aid, dong quai has long been touted to be able to reduce the risk of heart disease and stroke, lower high blood pressure, and promote blood circulation. New studies suggest this may be true, especially when dong quai is combined with ginseng. Dong quai is also high in vitamins A, E, and B12 and rich in flavonoids (antioxidants), coumarins (anticoagulants), and ferulate, useful in the prevention of thrombosis and cerebrovascular diseases. Dong quai is sometimes recommended as a strengthening treatment for the liver and kidneys, as some of the components of the herb seem to have blood-cleansing capabilities.

The only useful part of dong quai is the root, which is dried and sold in the form of tea, capsules, herbal mixes, powders, tinctures, and tablets. Some hospitals in China and Japan use injectable versions of dong quai, but these preparations are not available in Western countries. Dong quai is available over the counter in most pharmacies and sold in health food centers and vitamin shops. Dong quai is not recommended for people taking hormone medications, including oral contraceptives and estrogen, as the herb may interfere with the medication; patients taking blood-thinning medications should consult with their doctors before using dong quai.