Si Ni Tang (四逆汤) — Frigid Extremities Decoction

Si Ni Tang (Frigid Extremities Decoction) is the classical rescue formula in Chinese medicine for severe Yang collapse — cold hands and feet reaching the elbows and knees, weak or thready pulse, mental cloudiness and pallor. Originally formulated by Zhang Zhongjing in the Han dynasty Shang Han Lun (c. 220 CE), it uses just three herbs — Fu Zi, Gan Jiang and Zhi Gan Cao — but is one of the most powerfully warming formulas in the Chinese Materia Medica.

On this page

1. Overview
2. TCM pattern
3. Ingredients
4. Actions and indications
5. Dosing
6. Cautions and contraindications
7. Related formulas
8. Treatment at my clinic

1. Overview

Si Ni Tang (四逆汤) — Frigid Extremities Decoction — is a classical Chinese herbal formula in the Warm Interior category. Source: Shang Han Lun (Discussion of Cold Damage), c. 220 CE, by Zhang Zhongjing. I prescribe it as bespoke pharmaceutical-grade granules from Sun Ten in Taiwan at my clinic in Wokingham, Berkshire and via online herbal consultations.

2. TCM pattern

Devastated Yang with internal Cold. Characteristic signs: cold hands and feet reaching to the elbows and knees, aversion to cold, curled-up posture, weak or barely-palpable pulse, mental fogginess or drowsiness, cold sweats, watery diarrhoea with undigested food, pale swollen tongue with a white slippery coating.

3. Ingredients

1. Fu Zi — Aconite carmichaelii (processed) (9–15g) — chief herb; strongly warms and rescues Yang, dispels internal Cold, restores the Yang of the Heart, Spleen and Kidney
2. Gan Jiang — Zingiber officinale (dried ginger) (6–9g) — deputy; warms the Middle, assists Fu Zi in restoring Yang, warms the Spleen and Stomach
3. Zhi Gan Cao — Glycyrrhiza uralensis (honey-fried liquorice) (6g) — assistant and envoy; harmonises the formula, moderates the toxicity of Fu Zi, tonifies Middle Qi

4. Actions and indications

Principal actions

1. Restores devastated Yang
2. Warms the Middle and dispels Cold
3. Rescues from Yang collapse

Indications

1. Yang collapse with cold hands and feet reaching the elbows and knees
2. Aversion to cold with a strong desire to curl up
3. Weak, thready or barely-palpable pulse
4. Mental fogginess and lack of vitality
5. Watery diarrhoea containing undigested food
6. Cold sweats and pallor

5. Dosing

As decoction, once daily. Modern granule practice: 6–9g per day of the granule concentrate divided across two doses. Duration is short in acute Yang collapse (2–7 days) and adjusted downward as Yang recovers.

6. Cautions and contraindications

1. Contains processed Aconite (Fu Zi) — must be prescribed only by a qualified herbalist; never self-prescribe.
2. Contraindicated in true Heat masquerading as Cold (Yin excess with Yang trapped internally).
3. Contraindicated in pregnancy.
4. Not for Yin-deficiency “false cold” presentations.
5. Fu Zi requires correct sourcing (processed pao fu zi) and correct pre-cooking — do not use raw Aconite.

7. Related formulas

• Tong Mai Si Ni Tang — a stronger variant for more severe Yang collapse
• Bai Tong Tang — adds Cong Bai to guide Yang out to the exterior
• Shen Fu Tang — adds Ren Shen for concurrent Qi collapse

8. Treatment at my clinic

I prescribe Si Ni Tang where the TCM pattern above matches the patient’s presentation, typically as part of a wider prescription tailored to the individual. Return to the Chinese herbal formulas directory or the Chinese herbal medicine main page.