When the body tenses up

Calves that tighten, pulling sensations in the legs after exertion, a belly that knots up when fatigue or nervousness builds, muscles that struggle to relax… In TCM, these signs may be associated with Yin and Blood that no longer nourish the tendons. According to tradition, the Liver stores Blood and governs the tendons: when this Blood runs short, the tendons lose their suppleness and contract. The Spleen, the source of Blood, can no longer replenish it fully.

Shao Yao Gan Cao Tang, the “Peony and Licorice Decoction”, appeared around the year 200, at the end of the Eastern Han, in the Shang Han Lun (《伤寒论》) by Zhang Zhongjing (张仲景). It is one of the shortest formulas in the pharmacopoeia, and its pair of ingredients is among the most famous in the tradition: it lies at the heart of Gui Zhi Tang and Si Ni San. In Japan, Kampo medicine still uses it under the name Shakuyaku-kanzō-tō.

Sour and sweet give rise to Yin

The formula embodies better than any other a principle of the tradition: sour and sweet combined give rise to Yin (酸甘化阴). White peony, sour, gathers and retains; licorice, sweet, relaxes what tenses up. From their meeting arise the Fluids that give the tendons back their suppleness.

Nourishes the Blood and softens the Liver: White peony enters the Liver: it nourishes Blood, preserves Yin and, in the time-honoured expression, softens the Liver (柔肝).

Harmonises the Liver and Spleen: Licorice supports Spleen Qi, from which arises the Blood the Liver needs, and peony moderates the Liver so that it no longer weighs on the centre.

Helps restore suppleness: According to tradition, sweetness moderates what is tense (甘缓): with peony, licorice helps muscles and tendons regain their suppleness.