Xiao Ban Xia Tang (小半夏汤) — Minor Pinellia Decoction

On this page

1. Overview
2. TCM pattern
3. Key herbs
4. Formula actions
5. Conditions treated
6. Comparisons with related formulas
7. Modifications
8. Cautions

Overview

Xiao Ban Xia Tang — the Minor Pinellia Decoction — is one of Zhang Zhongjing’s simplest and most elegant formulas, appearing in the Jin Gui Yao Lue (Essentials from the Golden Cabinet, c. 220 CE). It is just two herbs — Ban Xia and Sheng Jiang — in substantial doses. Despite its simplicity it is one of the most reliable formulas in the materia medica for the specific picture of vomiting^[12] of clear fluid from Phlegm-Damp obstructing the middle burner.

Zhang Zhongjing wrote: “When the patient has vomiting of clear fluid (tan yin) due to retained thin fluids, Xiao Ban Xia Tang governs it.” The formula remains the foundation for treating tan yin (Phlegm-fluid) vomiting more than 1,800 years later.

The formula’s power lies in the unusual large dose of Sheng Jiang — classically a quarter pound — which both warms the Stomach and counteracts any toxicity of the Ban Xia. Ban Xia descends rebellious Stomach Qi and dries Damp; Sheng Jiang adds warmth and harmonising action. Together they form the most economical anti-emetic formula in TCM, and are the base from which many larger anti-emetic formulas (Xiao Ban Xia Jia Fu Ling Tang, Da Ban Xia Tang) are built.

I prescribe Xiao Ban Xia Tang as part of bespoke herbal formulas from pharmaceutical-grade granules sourced from Sun Ten in Taiwan.

TCM pattern

Xiao Ban Xia Tang is prescribed for Phlegm-fluid (tan yin) obstructing the Stomach:

• Vomiting of clear, watery fluid or thin phlegm — the cardinal sign
• Nausea often worse after drinking water or cold drinks
• Epigastric fullness with splashing sounds (succussion splash)
• No thirst (or thirst with reluctance to drink)
• Cold preferences — warm food and drink relieves the nausea
• Dizziness, vertigo^[22], palpitations in cases with significant fluid accumulation
• Tongue — moist, possibly slightly swollen, white slippery coat
• Pulse — slippery, possibly tight or thin

The pattern is common in morning sickness, motion sickness with vomiting of clear fluid, chemotherapy-induced nausea, hyperemesis gravidarum, recurrent gastritis with cold pattern, and acute viral gastroenteritis.

Key herbs

1. Ban Xia (Pinellia ternata, prepared, 6-24g) — chief; descends rebellious Stomach Qi; dries Damp; transforms Phlegm; stops vomiting. The single most important anti-emetic herb in Chinese materia medica.
2. Sheng Jiang (fresh ginger, large dose, 4-24g) — warms the Stomach; descends rebellious Qi; stops vomiting; counteracts any toxicity of Ban Xia

Formula actions

1. Descends rebellious Stomach Qi
2. Transforms Phlegm and dries Damp
3. Warms the Stomach
4. Stops vomiting and nausea

Conditions treated

1. Vomiting of clear watery fluid or thin phlegm — the primary indication; see nausea and vomiting
2. Morning sickness with cold/damp pattern (vomits clear fluid, cold extremities, no thirst) — see morning sickness
3. Hyperemesis gravidarum with Phlegm-fluid pattern (under specialist supervision)
4. Chemotherapy-induced nausea and vomiting — particularly vomiting of clear fluid
5. Motion sickness with vomiting of clear fluid
6. Acute gastroenteritis with cold-damp pattern
7. Gastroparesis with Phlegm-fluid retention
8. Recurrent vomiting in pregnancy with the Phlegm-fluid pattern
9. Cyclic vomiting syndrome with cold-damp pattern
10. Functional dyspepsia with nausea and clear fluid regurgitation — see digestive disorders
11. Vertigo with vomiting from Phlegm-fluid obstructing the upper body — see vertigo
12. Persistent hiccups with Phlegm-fluid pattern

Comparisons with related formulas

• Xiao Ban Xia Jia Fu Ling Tang — Xiao Ban Xia Tang plus Fu Ling; adds drainage of Damp through urination; for cases with dizziness, palpitations and stronger fluid accumulation.
• Wu Zhu Yu Tang — for Cold in the Stomach and Liver channel with vertex headache and vomiting of clear fluid; stronger Cold pattern.
• Er Chen Tang — broader Phlegm-Damp formula for cough^[10] and Phlegm; less focused on vomiting.
• Ban Xia Hou Po Tang — for Qi stagnation with Phlegm and plum-stone throat; different pattern.
• Da Ban Xia Tang — for severe vomiting from Stomach deficiency and Damp; adds Ren Shen and honey.
• Ju Pi Zhu Ru Tang — for vomiting and hiccups with Stomach Yin deficiency and mild Heat; opposite indication.

Modifications

• For vertigo and palpitations, add Fu Ling (becomes Xiao Ban Xia Jia Fu Ling Tang)
• For Stomach Qi deficiency with weakness, add Ren Shen and honey (becomes Da Ban Xia Tang)
• For Cold pattern with vertex headache, add Wu Zhu Yu (becomes Wu Zhu Yu Tang variant)
• For Stomach Heat overlay (red tongue, bitter taste), add Huang Lian and Zhu Ru
• For Stomach Yin deficiency overlay (dry mouth, peeled tongue), reduce Ban Xia and add Mai Men Dong
• For acid regurgitation, add Wu Bei Zi and Hai Piao Xiao
• For morning sickness, use minimal effective dose; modify with Sha Ren and Zi Su Geng

Cautions

Ban Xia is mildly toxic in unprocessed form; pharmaceutical-grade preparations from reputable suppliers use properly processed Zhi Ban Xia. Self-collecting or using unprocessed Ban Xia is dangerous.

Not appropriate for Stomach Yin deficiency vomiting (dry retching with little vomit, peeled tongue, red dry tongue) — the drying Ban Xia worsens Yin deficiency. Use Ju Pi Zhu Ru Tang or Mai Men Dong Tang instead.

Not appropriate for Stomach Heat vomiting with bitter taste, yellow vomit and red tongue with yellow coat. Use Huang Lian or Zhu Ru-based formulas.

Use cautiously in pregnancy — Ban Xia is traditionally avoided in pregnancy but is widely used at appropriate dose for severe pregnancy vomiting under qualified supervision. Always consult a qualified TCM practitioner trained in pregnancy.

Always consult a qualified Chinese herbalist registered with the RCHM.

Prefer to be treated from home? Chinese herbal medicine online consultations are available throughout the UK and worldwide.

References

[10] Lee B, Kwon CY, Suh HW, Kim YJ, Kim KI, Lee BJ, Lee JH. Herbal medicine for the treatment of chronic cough: a systematic review and meta-analysis. Front Pharmacol. 2023 Oct 17;14:1230604. https://doi.org/10.3389/fphar.2023.1230604. PMID: 37920213.

[12] Zhai X, He Q, Chen M, Yu L, Tong C, Chen Y, et al. Pinellia ternata-containing traditional Chinese medicine combined with 5-HT3RAs for chemotherapy-induced nausea and vomiting: A PRISMA-compliant systematic review and meta-analysis of 22 RCTs. Phytomedicine. 2023 Jul;115:154823. https://doi.org/10.1016/j.phymed.2023.154823. PMID: 37099981.

[22] Guo Z, Su Z, Wang Z, Luo X, Lai R. The effect of Chinese herbal medicine Banxia Baizhu Tianma Decoction for the treatment of vertebrobasilar insufficiency vertigo: A systematic review and meta-analysis of randomized controlled trials. Complement Ther Med. 2017 Apr;31:27-38. https://doi.org/10.1016/j.ctim.2017.01.004. PMID: 28434468.