ST 40 — Fēng Lóng (丰隆) — Bountiful Bulge

ST 40 (Stomach 40; Fenglong, “Bountiful Bulge”) is the Luo-Connecting point of the Stomach meridian and the primary acupuncture point for transforming phlegm and resolving damp anywhere in the body. Located halfway between the lower border of the patella and the lateral malleolus, two finger-widths lateral to the anterior crest of the tibia, it is used clinically for productive cough, sinus congestion, asthma, oedema, dizziness from phlegm-damp, foggy thinking, weight gain with damp accumulation, PCOS and any condition involving thick mucus or fluid retention.

On this page

1. Overview
2. Location
3. Actions
4. Indications
5. Needling
6. Clinical notes
7. Common point combinations
8. Treatment at my clinic
9. Frequently asked questions about ST 40

1. About ST 40 (Feng Long)

ST 40 — Fēng Lóng (丰隆) — is an acupuncture point on the Stomach meridian. Its English name, Bountiful Bulge, refers to the prominent muscle mass at the point’s location on the lateral leg. It is the Luo-Connecting point of the channel and, in classical and modern TCM practice alike, the single most important point for transforming phlegm and resolving damp. It is used regularly in acupuncture practice for productive cough, sinus problems, PCOS, dizziness from phlegm and the foggy thinking that often accompanies damp-phlegm patterns.

I am Dr (TCM) Attilio D’Alberto, a member of the British Acupuncture Council with over 25 years of clinical experience. I use ST 40 as part of individually tailored acupuncture prescriptions at my clinic in Wokingham, Berkshire.

2. ST 40 location

8 cun above the tip of the lateral malleolus, one finger-breadth lateral to ST 38 (Tiaokou), two finger-breadths lateral to the anterior crest of the tibia. To find it: measure halfway between the lower border of the kneecap and the outer ankle bone; the point sits two finger-widths lateral to the shin bone in the bulk of the tibialis anterior muscle. The point is often noticeably firm or tender in patients with phlegm-damp patterns.

3. Actions

1. Resolves Phlegm from any part of the body — the most important Phlegm-resolving point
2. Harmonises the Stomach and descends rebellious Qi
3. Calms the Mind and resolves Phlegm misting the Heart
4. Activates the meridian and relieves pain

4. Indications

1. Phlegm obstruction — the primary point for all Phlegm disorders
2. PCOS — resolves Phlegm-Damp obstructing ovulation
3. Cough and asthma with copious phlegm
4. Dizziness and vertigo from Phlegm
5. Nausea and vomiting from Phlegm in the Stomach
6. Mania and mental disturbance from Phlegm misting the Heart
7. Goitre and lymph node swellings from Phlegm accumulation
8. Obesity from Phlegm-Damp

5. Needling

Perpendicular insertion 1.0–2.0 cun. Strong De Qi often achieved with reduction technique — ST 40 typically requires firmer stimulation than tonifying points to effectively transform phlegm. The point is often noticeably firm to palpation in phlegm-damp patients, softening over a course of treatment as the pattern resolves.

Important: Acupuncture should only be performed by a fully qualified practitioner. Never attempt self-needling. All needles I use are sterile, single-use and disposed of immediately after treatment in a clinical sharps container.

6. Clinical notes

ST 40 is the Luo-Connecting point of the Stomach meridian and the single most important point in acupuncture for resolving Phlegm — both substantial Phlegm (the productive sputum of chronic cough, sinus catarrh) and insubstantial Phlegm (the TCM concept underlying dizziness, foggy thinking, mental dullness, lymph stagnation, lipomas and the cognitive symptoms of phlegm misting the Heart).

It is classically paired with SP 9 (Yin Ling Quan) — the most important damp-resolving point — to form the textbook combination for any phlegm-damp pattern. This pairing is central to acupuncture treatment of PCOS, where the Phlegm-Damp pattern is one of the commonest underlying mechanisms preventing ovulation. ST 40 is also a key point in modern weight-management acupuncture protocols, where its phlegm-damp-resolving action addresses the metabolic sluggishness that contributes to fat accumulation.

7. Common point combinations

1. ST 40 + SP 9 (Yin Ling Quan) — the classical phlegm-damp combination. Resolves both Phlegm (ST 40) and Damp (SP 9) simultaneously, used for PCOS, productive cough, weight gain with damp pattern and chronic sinus congestion.
2. ST 40 + LU 5 (Chize) — the standard combination for productive cough and chronic bronchitis with copious phlegm.
3. ST 40 + CV 12 (Zhongwan) — the “Phlegm root” combination, addressing the Stomach origin of Phlegm formation. Used for stomach-pattern phlegm, nausea and digestive sluggishness.
4. ST 40 + HT 7 (Shenmen) — the “Phlegm misting the Heart” pair for anxiety with foggy thinking, mania, mental dullness and the cognitive symptoms of chronic damp-phlegm.
5. ST 40 + BL 13 (Feishu) — the Lung back-shu point with ST 40 for chronic respiratory phlegm conditions, including asthma and chronic bronchitis.
6. ST 40 + SP 3 (Taibai) — the Spleen Yuan-Source point with ST 40 for the Spleen-deficiency origin of phlegm-damp obesity and chronic dampness.

8. Treatment at my clinic

I use ST 40 as part of tailored acupuncture prescriptions for conditions including PCOS, weight management, chronic sinusitis, asthma, productive cough, dizziness from phlegm, foggy thinking and the cognitive symptoms of phlegm-damp patterns. Each treatment is individually designed following a full TCM assessment.

I see patients in person at my clinic in Wokingham, Berkshire. Visit the prices page for consultation fees. Return to the acupuncture points directory or the acupuncture main page.

9. Frequently asked questions about ST 40

What are the acupuncture points ST40 used for?

The acupuncture points ST40 (Fenglong) are used primarily to transform Phlegm and resolve Damp anywhere in the body. The most common clinical uses are PCOS with phlegm-damp pattern, productive cough, chronic sinusitis, asthma, dizziness from phlegm, foggy thinking, weight management with damp accumulation, and the mental dullness of phlegm misting the Heart. Acupuncture points ST40 are the single most important Phlegm-resolving point in Chinese medicine.

Where do you press acupressure points ST40?

To find the acupressure points ST40: measure halfway between the lower border of your kneecap and the outer ankle bone. From that midpoint, move two finger-widths lateral (away from the shin bone) into the bulk of the muscle on the outer side of the leg. Apply firm pressure with your thumb for 1–3 minutes. Acupressure points ST40 are often noticeably firm or tender in patients with phlegm-damp patterns.

Can ST 40 help with PCOS?

Yes — ST 40 is one of the core acupuncture points used for PCOS, particularly the common Phlegm-Damp pattern that presents with weight gain, irregular or absent ovulation, oily skin, acne and a heavy sluggish quality. It is paired with SP 9 (Yin Ling Quan) for the classical phlegm-damp-resolving combination. PCOS treatment typically uses ST 40 over a course of 12–16 weeks alongside dietary changes.

Can ST 40 help with weight loss?

ST 40 is a key point in acupuncture protocols for weight management, particularly when weight gain is associated with a phlegm-damp pattern (heavy, sluggish quality, oily skin, foggy thinking, bloating). Acupuncture is not a magic solution for weight loss, but ST 40 can support the underlying metabolic sluggishness that makes weight loss harder, particularly alongside diet and lifestyle changes.

Can ST 40 help with cough and phlegm?

Yes — ST 40 is the primary acupuncture point for productive cough with copious phlegm, chronic sinus congestion and asthma with sputum production. It is used clinically for chronic bronchitis, post-viral cough that lingers with phlegm, and the productive cough that follows winter colds. Combined with LU 5 (Chize) for the strongest effect on respiratory phlegm.

What does ST 40 mean in Chinese?

ST 40 is called Fēng Lóng (丰隆) in Chinese, which translates as “Bountiful Bulge”. The name refers to the prominent muscle mass at the point’s location on the lateral leg — a “bulge” of bountiful tissue.

Is ST 40 safe during pregnancy?

Yes — ST 40 is generally safe during pregnancy. It has no documented uterotonic effect and can be used for pregnancy-related phlegm conditions such as productive cough and excessive nasal mucus, under qualified care.