Pinggan Yuyin Qingre Formula

What It Is

Name and orientation

• The name “Pinggan Yuyin Qingre” can be broken down roughly as: “pacify the liver (Pinggan), nourish yin (Yuyin), [and] clear heat (Qingre).” It is a TCM herbal formula (often in granule / decoction form) used in TCM ophthalmology settings.
• Its full Chinese name is 平肝育阴清热方 (sometimes abbreviated PGYYQR).

Intended use / target condition

• In modern clinical TCM/ophthalmology research, this formula has been applied in patients with dry eye disease (DED), specifically in cases where dry eye is due to meibomian gland dysfunction (MGD) (i.e. evaporative-type dry eye), in people whose TCM pattern is diagnosed as “Yin deficiency with Yang hyperactivity / internal heat” (“阴虚阳亢”-型). journaltcm.cn

Empirical / clinical trial usage

• One stratified randomized controlled trial has been published (2023) involving 120 dry eye patients with MGD, comparing standard eye-drop therapy plus PGYYQR vs eye drops alone. journaltcm.cn
• Other smaller experimental / observational reports also exist, suggesting benefits in symptom relief, tear film stability, and TCM symptom scores. syfjxzz.com

Thus, PGYYQR is a TCM herbal formula proposed for a specific subtype of dry eye, especially when a Yin-deficiency + internal heat pattern is identified.

How It Works (Claims / Proposed Mechanisms)

Because this is in the domain of TCM and early-stage integrative research, the mechanistic understanding is a mixture of TCM theory, animal / in vitro / network pharmacology speculation, and limited human trial outcomes.

In TCM theory

• “Pinggan” (pacify liver): In TCM, the liver is often said to govern “wind” or to be involved in regulating fluid circulation and eye health. If the liver is considered “hyperactive” (especially in the Yang direction), that may generate internal heat or disturb yin/fluid balance.
• “Yuyin” (nourish yin): This refers to replenishing the yin, especially internal body fluids, moisturizing, and counterbalancing depletion or dryness.
• “Qingre” (clear heat): Clearing internal heat or inflammation or pathological heat that, in TCM terms, may injure yin or aggravate dryness, inflammation, or irritation.
• The idea is that by combining these actions, the formula addresses both the root (yin deficiency, internal heat) and the branch (symptoms of heat / inflammation) of the disease.

From biomedical / trial-based evidence

• The 2023 trial found that the group receiving PGYYQR showed better improvement than control (drops only) in certain endpoints: the meibomian gland secretion quality, palpebral margin scores, and average noninvasive tear breakup time (NITBUT). Europe PMC
• However, it did not show a statistically significant improvement in lipid layer thickness (LLT) compared with control.
• The authors interpret that PGYYQR may help by improving meibum quality (i.e. the secretion consistency, reducing clogging or poor lipid output), stabilizing tear film, thereby alleviating ocular dryness symptoms.
• Other reports (in experimental / observational settings) assert that the formula can reduce symptoms such as burning, itching, foreign body sensation, dryness, and also improve tear film stability and ocular surface health. zgsyfjxzz.ijournals.cn

Gaps / unknowns in mechanism

• Very few mechanistic studies exist (e.g. on molecular pathways, anti-inflammatory / antioxidant / lipid metabolism effects) specific to PGYYQR. The network pharmacology / herbal mechanism literature tends to generalize from components in “yin nourishment + heat clearing” herbs, but not always specifically this formula.
• Also, whether the improvements observed are due to specific direct actions on meibomian glands, or more systemic “balancing” effects, or even placebo / nonspecific supportive effects, remains unclear.

Why It’s Important (From a Health Perspective)

Unmet need in dry eye / MGD treatment

• Dry eye disease (especially the evaporative type due to meibomian gland dysfunction) is common and often chronic. Standard treatments include artificial tears, warm compresses, eyelid hygiene, omega-3s, sometimes antibiotics or anti-inflammatories, etc. Many patients still suffer symptoms or incomplete relief, or side effects.

Potential complementary approach

• PGYYQR represents a TCM-based complementary strategy targeted to a specific subtype (Yin deficiency with internal heat) that might provide incremental benefits, especially for patients whose conventional therapy is insufficient or whose TCM diagnosis suggests this pattern.

Symptom relief + tear film stability

• In the clinical trial, adding PGYYQR led to statistically greater improvement in meibomian secretion quality, palpebral margin score, and tear breakup time than control (drops alone). Europe PMC
• The “total effective rate” by TCM syndrome criteria was 84.7% in treatment group vs 50.9% in control. journaltcm.cn
• No adverse reactions were reported in that trial. Europe PMC

Aligns with modern integrative medicine trends

• There is growing interest in combining TCM formulations with standard ophthalmologic care (especially in China and parts of Asia). PGYYQR is an example of a formula that is being studied clinically in that integrative paradigm.

So, in short: PGYYQR is potentially important as a complementary herbal option (in the TCM / integrative medicine space) for improving symptoms and objective signs in a subset of dry eye / MGD patients, with good tolerability in small trials.

Considerations, Risks & Caveats

Because the evidence is still preliminary, many caveats and cautionary points apply. Here are considerations you should be aware of:

Limited high-quality evidence

• The trial(s) to date are relatively small (120 persons) and largely confined to Chinese settings; generalizability to other populations is uncertain.
• Some endpoints (e.g. lipid layer thickness) did not improve significantly. Europe PMC
• Long-term effects and safety beyond 8 weeks or so are not well documented.

Herbal product quality and standardization

• As with many TCM herbal formulas, variations in herb sourcing, processing, purity, adulteration, contamination (heavy metals, pesticides, misidentification) can occur.
• The dose, extraction method, granule vs decoction form, and batch-to-batch consistency may influence effects and safety.
• The regulatory oversight in different countries may vary (e.g. Australia, U.S., Europe).

Potential herb–drug interactions

• If someone is already on other ocular medications (anti-inflammatories, steroids, immunosuppressants, systemic drugs) or systemic medications, interactions are possible (either through hepatic metabolism or additive / antagonistic effects).
• Always evaluate possible interactions with any systemic conditions / medications before combining herbal formulas.

Pattern (TCM) matching is essential

• In TCM theory, formulas are prescribed not just for the disease label but for a pattern (syndrome). PGYYQR specifically is indicated for “Yin deficiency with Yang hyperactivity / internal heat” patterns. If a patient’s pattern is different (e.g. Yin deficiency without heat, or damp-heat, or Qi stagnation, etc.), PGYYQR might not be appropriate or could even exacerbate imbalance.
• An experienced TCM practitioner is needed to diagnose and monitor the pattern.

Safety / side effects / monitoring

• The published trial reported no observed adverse effects, no abnormalities in ECG or liver/kidney function. syfjxzz.com
• But absence of evidence is not evidence of absence. Herbal formulas can carry risks (allergic reactions, herb toxicity, interactions).
• In long-term use or in special populations (pregnancy, children, liver disease, kidney disease, immune disorders), extra caution is required.

Not a substitute for conventional care

• For moderate or severe dry eye / MGD, conventional interventions (lubricants, eyelid hygiene, thermal/mechanical therapies, prescription medications) remain standard of care. PGYYQR might be explored as adjunctive therapy, not sole therapy (unless under careful oversight).
• In conditions where dry eye is secondary to systemic disease (e.g. Sjögren’s, autoimmune conditions), underlying disease management is paramount.

Need for further research

• Larger, multicenter, longer-term randomized controlled trials (ideally in diverse populations) are needed.
• Mechanistic studies (on inflammation, lipid metabolism, lipid glandular structure, oxidative stress, etc.) would help validate or refine rationale.
• Safety surveillance over time is also needed.