A small, perennial herb found in Japan and the western regions of China, dong quai typically grows in ravines, river banks and coastal areas. The root of dong quai is considered one of the most honored and respected herbs in China. Experts believe it has been used in Asia for a minimum of 2,000 years to treat everything from circulatory problems to liver and respiratory conditions.
Recent studies show that dong quai dilates blood vessels, which can reduce blood pressure.
It has also shown to improve oxygen utilization in the liver, and increases the metabolism of glutamic acid and cysteine. Limited studies have employed dong quai as a means to promote formation of red blood cells, especially in patients with kidney problems. However, further studies need to be performed to confirm these findings. Three to four grams a day of dong quai are recommended for women. Powdered dong quai root is available in several forms, including capsules, tablets, tinctures and extracts.