The Premier Formula for Nourishing Blood and Regulating the Menstrual Cycle in Women: Si Wu Tang (Four-Substance Decoction)

Si Wu Tang (Four-Substance Decoction) first appeared in the late-Tang book "Prescriptions for Treating Injuries and Restoring Bones Handed Down by an Immortal" by Lan Daoren. It was a famous formula of TCM orthopedics and traumatology, with the actions of activating blood and resolving stasis, reducing swelling, and relieving pain.

Later, in the Song dynasty "Taiping Huimin Heji Jufang" (Prescriptions from the Taiping Imperial Pharmacy), Si Wu Tang was listed as an obstetrics-gynecology formula. Thereafter, in such renowned obstetrics-gynecology classics as the Song "Weisheng Jiabao Chanke Beiyao: Chanhou Fang" (Essentials for Postpartum), the Ming "Yifang Kaoyao: Tiaojing Yong Si Wu Tang" (On Using Si Wu Tang to Regulate the Menses), and the early-Qing "Jiyin Gangmu" (Outline of Gynecology), Si Wu Tang was extremely highly praised. In clinical practice, later generations found Si Wu Tang had outstanding efficacy for obstetric and gynecological diseases, especially women's irregular menstruation and infertility. Si Wu Tang thus became the number-one gynecological formula and is known as the sacred herb for women.

Si Wu Tang is composed of four herbs: rehmannia (Dihuang), Angelica sinensis (Danggui), Ligusticum chuanxiong (Chuanxiong), and peony (Shaoyao). Rehmannia is divided into prepared rehmannia (Shudihuang) and raw rehmannia (Shengdihuang); peony is divided into red peony (Chishao) and white peony (Baishao). Prepared rehmannia tends toward warming and tonifying; raw rehmannia both nourishes blood and cools blood. White peony both nourishes blood and softens the liver to stop pain, while red peony excels at activating blood and resolving stasis. Thus for women with a hot constitution, raw rehmannia is more suitable; for women with a cold constitution, prepared rehmannia is more suitable. For women with predominant blood stasis, red peony is preferable to white peony; for dysmenorrhea patients, white peony is more suitable. Of course, in each individual case, more detailed pattern differentiation is needed when prescribing.

If you fear bitterness and do not want to drink Chinese medicine, you can decoct Si Wu Tang, add a certain amount of honey, and simmer it into Si Wu Gao (Four-Substance Paste), then eat a few spoonfuls of the sweet paste at a time.

Si Wu Tang may also be modified according to the patient's specific condition to address problems more effectively. Tao Hong Si Wu Tang (Peach Kernel and Safflower Four-Substance Decoction) and Chai Huang Si Wu Tang (Bupleurum and Scutellaria Four-Substance Decoction) are two widely used derivative formulas.

Tao Hong Si Wu Tang adds peach kernel (Taoren) and safflower (Honghua) to Si Wu Tang, used for patients with heavy stasis. Chai Huang Si Wu Tang adds bupleurum (Chaihu) and scutellaria (Huangqin), used for patients who also have infectious disease. Some intractable gynecological inflammations can often be considered for treatment with these two derivative formulas.

Of course, some spleen-deficient patients may have spleen-strengthening herbs added on the basis of Si Wu Tang, such as Codonopsis (Dangshen), atractylodes (Baizhu), Poria (Fuling), licorice (Gancao), tangerine peel (Chenpi), and Pinellia (Banxia). The famous qi-and-blood dual-tonifying Bazhen Tang is precisely Si Wu Tang combined with the famous spleen-strengthening Sijunzi Tang (Four-Gentlemen Decoction) into one.

For severe blood deficiency and blood stasis, Si Wu Tang may be used together with salvia (Danshen). TCM has the saying that "a single Danshen functions like Si Wu Tang." Salvia activates and nourishes blood and is a commonly used clinical herb.