Ping Wei San — Calm the Stomach Powder

On this page

1. Overview
2. TCM pattern
3. Key herbs
4. Conditions treated
5. Cautions

Overview

Ping Wei San — Calm the Stomach Powder — is the foundational formula in Chinese herbal medicine for drying Dampness and strengthening the Spleen and Stomach. Dating to the Song Dynasty, its four simple herbs create a powerful formula that directly targets Damp obstructing the Middle Jiao — one of the most common pathological patterns in clinical practice, particularly in patients who consume a diet high in damp-generating foods or who live in damp environments. It serves as the base from which dozens of derivative Damp-resolving formulas are built.

TCM pattern

Prescribed for Damp obstructing the Spleen and Stomach (Middle Jiao), characterised by: a sensation of fullness and distension in the epigastrium and abdomen, nausea, heavy feeling in the body and limbs, fatigue, loose stools, a bland or absent sense of taste, a swollen tongue with thick greasy white coating, and a slow, slippery pulse.

Key herbs

1. Cang Zhu (Atractylodes lancea rhizome) — the most potent Damp-drying herb in TCM; strongly dries Dampness and strengthens the Spleen
2. Hou Po (Magnolia officinalis bark) — moves Qi, dries Dampness and reduces distension; particularly effective for bloating and fullness
3. Chen Pi (aged Citrus reticulata peel) — regulates Qi, dries Dampness and harmonises the Middle Jiao
4. Zhi Gan Cao (honey-fried Glycyrrhiza root) — harmonises the formula and moderates the drying herbs

Conditions treated

1. Bloating, abdominal distension and epigastric fullness from Damp obstructing the Middle Jiao
2. Nausea and poor appetite from Spleen-Damp
3. Digestive sluggishness and heavy limbs after eating damp-generating foods
4. IBS with Damp predominance
5. Long COVID with Phlegm-Damp brain fog and digestive symptoms

Warm and drying — use with caution in Yin deficiency or where fluid deficiency is present.

Cautions

Always consult a qualified Chinese herbalist registered with the Register of Chinese Herbal Medicine (RCHM). Online herbal consultations are available. See the prices page for costs.