Abstract:Using many kinds of modern instruments, we have measured the content of ferulic acid, eight trace elements, seventeen amino acids and water-soluble substances in various single drug decoctions, group-drug decoctions, and mixtures of various single drug decoctions of Radix Angelicae Sinensis, Radix Rehmanniae, Radix Paeoniae Alba and Rhizoma Chuanxiong that make up the decoction Siwu Tang. Absorption peaks in ultraviolet spectra have also been measured.