Bai He Gu Jin Tang (百合固金汤): The Lily Bulb Formula for Dry Cough, Lung Yin Deficiency, and Hoarseness

What Is Bai He Gu Jin Tang?

Bai He Gu Jin Tang (百合固金汤), translated as “Lily Bulb Metal-Securing Decoction,” is one of the most important formulas in TCM for nourishing Lung and Kidney Yin. Recorded in the Qing Dynasty text Yi Fang Ji Jie (医方集解, “Collection of Medical Formulas with Explanations”), it is specifically designed for the pattern where the Lungs and Kidneys are both depleted of their Yin — the cooling, moistening, and resting aspects of these organs.

The name breaks down as:

• Bai He (百合) = Lily Bulb, the chief herb
• Gu Jin (固金) = “Secure Metal” — Metal is the Five Element associated with the Lungs
• The formula “secures” the Lungs by deeply nourishing their Yin reserves

The Pattern It Treats

Lung-Kidney Yin Deficiency (肺肾阴虚)

In Five Element theory, the Lungs (Metal) and Kidneys (Water) have a mother-child relationship: Metal generates Water. When Lung Yin is deficient, it cannot adequately nourish Kidney Yin, and when Kidney Yin (the body’s deepest Yin reserve) is depleted, it cannot support the Lungs. Bai He Gu Jin Tang addresses both levels simultaneously.

Key symptoms:

• Chronic dry cough, sometimes with blood-streaked sputum
• Hoarseness or loss of voice
• Dry, sore throat
• Dry mouth
• Night sweats
• Low-grade afternoon fever (五心烦热 — hot palms, soles, and chest)
• Red tongue with little or no coating
• Thin, rapid pulse

The Herbs

Herb	Chinese	Role	Action
Bai He	百合	Chief	Nourishes Lung Yin, calms the spirit
Sheng Di Huang	生地黄	Deputy	Nourishes Kidney Yin, cools blood
Shu Di Huang	熟地黄	Deputy	Deeply nourishes Kidney Yin and Jing
Mai Men Dong	麦门冬	Deputy	Nourishes Lung and Stomach Yin
Xuan Shen	玄参	Deputy	Nourishes Yin, clears deficiency heat
Bai Shao	白芍	Assistant	Nourishes Blood, softens the Liver
Dang Gui	当归	Assistant	Nourishes and invigorates Blood
Bei Mu	贝母	Assistant	Transforms phlegm, stops cough
Jie Geng	桔梗	Assistant	Carries herbs to the Lungs, opens the throat
Gan Cao	甘草	Harmonizer	Harmonizes, soothes the throat

How the Formula Works

The formula operates on three levels:

Level 1: Nourish Lung Yin (The Surface)

Bai He (Lily Bulb) is the star — it gently nourishes Lung Yin without being cloying. Mai Men Dong reinforces this action. Together, they restore moisture to the dry, irritated Lung tissue.

Level 2: Nourish Kidney Yin (The Root)

Sheng Di Huang and Shu Di Huang deeply nourish Kidney Yin — the body’s deepest reserve. Because Kidney Yin supports Lung Yin (Water nourishes Metal in Five Element theory), treating the root ensures lasting improvement.

Level 3: Clear Heat and Resolve Phlegm

Xuan Shen clears deficiency heat. Bei Mu transforms the sticky, hard-to-expectorate phlegm that comes with Yin deficiency. Jie Geng guides the formula to the upper body and opens the throat.

Dang Gui and Bai Shao ensure that Blood is also nourished — in TCM, Blood and Yin are closely related, and nourishing one supports the other.

Clinical Applications

1. Chronic Dry Cough

The primary use. Especially effective for:

• Dry, hacking cough that has persisted for weeks or months
• Cough that worsens at night or when talking
• Cough with sticky, scanty sputum that is hard to expectorate
• Post-viral dry cough that won’t resolve
• Cough in the elderly or after prolonged illness

2. Hoarseness and Voice Loss

• Hoarse, raspy voice
• Voice that tires easily
• Loss of voice after prolonged speaking
• Common among teachers, singers, and public speakers
• The combination of Yin nourishment + Jie Geng throat-opening action is especially effective

3. Blood-Streaked Sputum (咳血)

• Small amounts of blood in sputum
• Pink or rust-colored sputum
• Caused by deficiency heat damaging the Lung vessels
• The Yin-nourishing and blood-cooling herbs address the root

4. Sore, Dry Throat

• Chronic dry throat that feels scratched or raw
• Worse at night or upon waking
• Throat feels better with warm drinks
• Not from acute infection, but from chronic dryness

5. Post-Tuberculosis Recovery

Historically used for recovery from “Lung consumption” (肺痨), the TCM term for tuberculosis-like wasting diseases. While TB requires modern medical treatment, this formula supports recovery from the Yin-depleted state that follows severe respiratory illness.

Comparison with Related Formulas

Feature	Bai He Gu Jin Tang	Qing Zao Jiu Fei Tang	Mai Men Dong Tang
Primary pattern	Lung-Kidney Yin deficiency	Warm-dryness damaging Lungs	Lung-Stomach Yin deficiency
Depth	Deep — reaches Kidney	Surface-Middle — Lung level	Middle — Lung-Stomach
Key symptom	Dry cough + hoarseness + bloody sputum	Dry cough + thirst + headache	Chronic cough + dry heaves
Number of herbs	10	10	6
Kidney focus	Strong	None	Minimal
Acute vs chronic	Chronic	More acute	Chronic

Forms and Administration

Form	Best For
Decoction	Active symptoms — most effective
Patent pills	Long-term maintenance and prevention
Honey pills	Traditional form — slow, sustained release

The decoction is traditionally taken warm, in divided doses, 2–3 times daily. For chronic conditions, it may be taken for 2–4 weeks before reassessing.

Modern Research

Studies on Bai He Gu Jin Tang and its components have found:

• Antitussive — suppresses cough reflex
• Anti-inflammatory — reduces airway inflammation
• Mucolytic — helps thin and expel thick sputum
• Hemostatic — helps stop minor bleeding in the respiratory tract
• Immunomodulatory — supports immune function in the respiratory mucosa
• Antioxidant — protects lung tissue from oxidative damage

Precautions

• Spleen deficiency with dampness — the heavy Yin-nourishing herbs can cause bloating, loose stools, or nausea in patients with weak digestion
• External cold/flu — do not use during active exterior conditions; the tonifying herbs may trap the pathogen
• Phlegm-damp cough — not suitable when cough is wet with copious clear or white phlegm (this formula is for dry, deficient patterns)
• Early-stage cough — only appropriate for chronic or deficiency-type coughs

Why Bai He Gu Jin Tang Matters

Chronic dry cough is one of the most common lingering complaints after respiratory infections, and one of the most frustrating — it can persist for months after the initial illness has resolved. Bai He Gu Jin Tang addresses this by going beyond symptomatic treatment: it rebuilds the Lung’s moisture reserves at both the Lung level (surface) and the Kidney level (root). For anyone who has experienced a dry, tickling cough that won’t go away, this formula represents TCM’s most elegant solution.

Related Reading

• Sang Ye: Mulberry Leaf for Lungs
• Mai Dong: Ophiopogon for Yin
• Sheng Di Huang: Raw Rehmannia
• Five Elements Theory
• Lung Health in TCM