BACKGROUND
Samul-tang (Si-Wu-tang in Chinese, Shimotsu-to in Japanese), widely used in eastern Asia, is composed of Angelica gigas (Angelicae Gigantis Radix), Cnidium officinale (Cnidii Rhizoma), Paeonia lactiflora (Paeonia Radix) and Rehmannia glutinosa (Rehmanniae Radix Preparata). Paeoniflorin,