BU FEI TANG

Lung Qi-Tonifying & Lung-Consolidating • Essence-Nourishing & Cough-Relieving Formula

Symptoms

Chronic Cough: Persistent or recurrent cough, typically weak in character, which may worsen with physical exertion, prolonged talking, fatigue, or chronic illness.

Shortness of Breath: Shallow breathing, breathlessness on exertion, or difficulty sustaining a deep breath, reflecting weakness of Lung Qi and impaired respiratory function.

Weak Voice & Fatigue: Low or weak voice, reluctance to speak, reduced stamina, tiredness, and general weakness associated with deficient Lung Qi.

Respiratory Weakness: Recurrent or prolonged respiratory symptoms, particularly following chronic illness, where the Lung's dispersing and descending functions remain weakened.

Spontaneous Sweating: Easy sweating, especially following mild activity, associated with deficient Lung Qi and insufficient consolidation of the exterior.

Lung–Kidney Deficiency Signs: In more chronic presentations, respiratory weakness may coexist with lower back weakness, reduced vitality, or difficulty maintaining a deep inhalation, reflecting insufficient support of the Kidney to the Lung.

Dryness & Deficiency: Chronic deficiency may be accompanied by a relatively dry throat or cough with scanty sputum, particularly when prolonged illness has consumed the body's nourishing substances.

Tongue: Pale or pale-red, potentially slightly dry in prolonged deficiency, with a thin coating.

Pulse: Weak (Ruo), deficient (Xu), or thready (Xi), particularly at the Lung position; deeper weakness may be present when Kidney deficiency is involved.

Ingredients

Shu Di Huang (Rehmannia glutinosa – prepared root)
Raw Herbs 24g | Granules 28.6g

Huang Qi (Astragalus membranaceus)
Raw Herbs 24g | Granules 28.6g

Ren Shen (Panax ginseng)
Raw Herbs 9g | Granules 10.7g

Zi Wan (Aster tataricus)
Raw Herbs 9g | Granules 10.7g

Sang Bai Pi (Morus alba – root bark)
Raw Herbs 12g | Granules 14.3g

Wu Wei Zi (Schisandra chinensis)
Raw Herbs 6g | Granules 7.1g

Posology

Granules: 3 to 9g per day, divided into two or three doses.

Raw Herbs: Boil in 1000–1200ml of water and drink 1 to 3 cups per day.

Description

Bu Fei Tang (Tonify the Lungs Decoction) is a traditional formula designed for patterns of Lung Qi Deficiency accompanied by chronic weakness of respiratory function, particularly when prolonged deficiency has begun to involve the deeper relationship between the Lung and Kidney systems.

From a TCM and Jing Fang perspective, the formula addresses both the root (Ben) and branch (Biao) of the pattern. The root lies in insufficient Qi and nourishing substances failing to adequately support the Lung, while the branch manifests as impaired descending of Lung Qi, resulting in cough, shortness of breath, weak respiration, and reduced respiratory endurance.

Huang Qi strongly supplements Lung and Spleen Qi, supports the Wei Qi, strengthens the exterior, and helps restore the Lung's dispersing function. At 24g, it forms one of the principal tonifying components of the formula.

Ren Shen powerfully tonifies the Yuan Qi and strengthens both Lung and Spleen Qi. In respiratory deficiency, it supports the Lung's ability to govern Qi and respiration while reinforcing the constitutional Qi necessary for sustained respiratory function.

Together, Huang Qi and Ren Shen rebuild the functional Qi of the Lung and provide the energetic foundation upon which the remaining herbs act.

Shu Di Huang, also present at 24g, nourishes Blood and enriches Kidney Yin and Essence (Jing). Its inclusion deepens the formula beyond simple Lung Qi tonification. According to the traditional relationship between the Lung and Kidney, the Lung governs respiration and sends Qi downward, while the Kidney assists in receiving and grasping Qi. By nourishing the Kidney and Essence, Shu Di Huang supports the deeper root of chronic respiratory deficiency, particularly in long-standing or constitutionally weak presentations.

The combination of Shu Di Huang with Ren Shen and Huang Qi therefore provides a broad supplementation strategy: Qi is strengthened while the deeper nourishing foundation of Blood, Yin, and Essence is supported.

Wu Wei Zi enters the Lung and Kidney systems and has an astringent, consolidating action. It helps secure Lung Qi, reduce its excessive leakage, and support the Kidney's ability to receive Qi. This makes it particularly valuable in chronic cough and shortness of breath associated with deficiency.

The pairing of Wu Wei Zi and Shu Di Huang further strengthens the Lung–Kidney relationship: Shu Di Huang nourishes the deeper constitutional root, while Wu Wei Zi consolidates and prevents further dissipation.

Zi Wan moistens and regulates the Lung, transforms Phlegm, and directs Lung Qi downward to relieve cough. Its descending action ensures that the strong tonifying components of the formula do not obstruct the normal movement of Lung Qi.

Sang Bai Pi directs rebellious Lung Qi downward and helps relieve cough and wheezing. Its descending and regulating character balances the rich tonifying herbs and helps restore the physiological direction of Lung Qi.

The overall structure therefore combines three complementary therapeutic strategies:

Tonify and rebuild: Huang Qi, Ren Shen and Shu Di Huang strengthen Qi and replenish the deeper nourishing foundation.

Consolidate and secure: Wu Wei Zi prevents excessive loss of Lung Qi and supports the Lung–Kidney axis.

Restore descending Lung Qi: Zi Wan and Sang Bai Pi address the branch manifestation by directing Lung Qi downward and relieving cough and wheezing.

In classical pattern language, Bu Fei Tang is therefore particularly appropriate where Lung Qi Deficiency constitutes the primary pattern, chronic deficiency has weakened the deeper Lung–Kidney relationship, and Lung Qi fails to descend normally.

The therapeutic principle can be summarized as:

Tonify Lung Qi • Nourish Kidney Essence • Consolidate the Lung • Restore descending Qi • Relieve chronic cough and dyspnoea

Contraindications

Not appropriate as a primary formula for acute exterior patterns where an unresolved pathogenic factor remains at the surface.

Use with caution in pronounced Phlegm-Heat or Lung Heat patterns presenting with fever, thick yellow sputum, marked thirst, a red tongue, or a yellow/greasy coating.

Because Wu Wei Zi is strongly astringent, caution is appropriate when an external or internal pathogenic factor still needs to be dispersed or expelled.

Due to the rich and cloying nature of Shu Di Huang, use with caution in patients with significant Spleen Qi Deficiency accompanied by Dampness, abdominal fullness, poor appetite, loose stools, or a thick greasy tongue coating.

The formula should be differentiated from predominantly excess patterns of cough and wheezing, particularly those caused by acute Wind invasion, substantial Phlegm accumulation, or intense Lung Heat.