Rongtong Dictionary · Formula

Yinqiao Powder: Wu Jutong's 'Acrid-Cool Balanced Formula,' the Defensive-Level Logic, the Three Acrid-Cool Formulas, and Modern Evidence

Published and reviewed 2026-07-09

Yinqiao (Honeysuckle-Forsythia) Powder comes from the Qing warm-disease master Wu Jutong's Wenbing Tiaobian, where it is the opening formula of the entire work and the representative 'acrid-cool balanced formula,' the hallmark of the 'acrid-cool release-the-exterior' method. Following the Neijing dictum 'for wind excess within, treat with the acrid-cool, assisted by the bitter-sweet,' it is built from honeysuckle, forsythia, mint, arctium, schizonepeta, fermented soybean, platycodon, lophatherum, phragmites, and licorice for the defensive-level pattern of early warm disease (fever, slight aversion to wind-cold, sore throat, thirst, and a floating rapid pulse). It is both a model of 'the light can dispel repletion,' acrid-cool compatibility, and warm-disease triple-burner differentiation, and a case where a 'defensive-level pattern' is not a modern diagnosis of influenza or COVID-19 — acrid-cool release requires differentiation, and acute febrile illness must be diagnosed and treated by modern medicine.

Origin: the opening formula of the Wenbing Tiaobian

Yinqiao Powder comes from the Qing synthesizer of the warm-disease school, Wu Jutong (Wu Tang, 1758-1836), and his Wenbing Tiaobian (Systematic Differentiation of Warm Diseases), where it is the very first formula of the upper-burner chapter and the one Wu called the 'acrid-cool balanced formula.' The text prescribes it for 'taiyin wind-warmth, warm-heat, warm-epidemic, and winter-warmth, at the outset, with fever but no aversion to cold and with thirst' — that is, early warm disease with the pathogen attacking the lung and defensive level. It is the most representative formula of the 'acrid-cool release-the-exterior' method and holds a very high place in the history of warm-disease treatment.

Wu stated the formula's rationale himself: 'respectfully following the Neijing teaching, for wind excess within, treat with the acrid-cool, assisted by the bitter-sweet; for heat excess within, treat with the salty-cold, assisted by the sweet-bitter.' Its lineage traces to Li Dongyuan's Puji Xiaodu Yin — amid epidemics, Wu inherited predecessors' approach of dispersing wind-heat and giving the pathogen an exit, developing this representative warm-disease formula, embodying 'using ancient methods without being bound to ancient formulas.' The original was designed as a powder (forsythia and honeysuckle one liang each, platycodon, mint, and arctium six qian each, decocted in fresh phragmites broth, 'taken as soon as the aroma emerges, not over-boiled'). This page identifies the entity only and offers no dose conversion or preparation procedure.

Composition: the subtlety of 'acrid-warm within the acrid-cool'

Ten ingredients: honeysuckle (Lonicerae Japonicae Flos, sovereign), forsythia (Forsythiae Fructus, sovereign), mint (Menthae Herba, minister), arctium (Arctii Fructus, minister), schizonepeta spike (Schizonepetae Spica, assistant), fermented soybean (Sojae Semen Praeparatum, assistant), platycodon (Platycodonis Radix, assistant-envoy), lophatherum (Lophatheri Herba, assistant), phragmites (Phragmitis Rhizoma, assistant), and raw licorice (Glycyrrhizae Radix, assistant-envoy).

In the textbook reading, honeysuckle and forsythia are heavily used as sovereigns — aromatic, they disperse wind-heat, clear heat and resolve toxin, and dispel turbidity, addressing warm pathogens' tendency to gather into toxin and mix with turbid qi; mint and arctium, acrid-cool, vent the exterior, clear the head and eyes, and relieve the throat as ministers. The formula's greatest subtlety is pairing in schizonepeta spike and fermented soybean — though acrid-warm, they are 'warm but not drying,' compensating for the weaker dispersing power of acrid-cool herbs and aiding the sovereigns and ministers to vent the pathogen; and acrid-warm with cold-cool avoids warm-dry heat-aiding, while cold-cool with acrid-warm avoids cold congealing and trapping. This is Wu's 'protecting against deficiency in advance, purely clearing the upper burner without invading the middle and lower, with no fault of opening the door to the thief and the ability to clear away repletion.' Lophatherum and phragmites clear heat and engender fluid, platycodon and licorice diffuse the lung and relieve the throat, and licorice harmonizes. Chiefly acrid-cool, assisted by acrid-warm, together an 'acrid-cool balanced formula' that vents the exterior, clears heat, and resolves toxin.

Pattern, not disease: 'defensive-level pattern' is not influenza or COVID-19

The textbook mechanism is 'early warm disease, pathogen at the defensive level.' Warm-heat pathogens enter through the nose and mouth and first attack the lung and defensive level; defensive qi constrained with disordered opening and closing brings fever, slight aversion to wind-cold, and absence or inhibition of sweat; warm pathogens harassing upward bring headache; heat damaging fluid brings thirst; pathogenic heat scorching the throat brings sore throat; a floating rapid pulse marks the warm pathogen at the exterior. The method is 'acrid-cool vent the exterior, clear heat and resolve toxin.' (Note: whether a warm pathogen can 'constrain' defensive qi is debated within the warm-disease field; this page follows the mainstream textbook account.)

Here 'defensive level,' 'warm disease,' and 'defensive qi' are traditional functional constructs — arising from the warm-disease defensive-qi-nutritive-blood and triple-burner differentiation systems, emphatically not synonyms for influenza, the common cold, pneumonia, measles, encephalitis, COVID-19, or any modern diagnosis. Although Yinqiao Powder was widely recommended in successive epidemic (including COVID-19) TCM protocols for those 'differentiated as a wind-heat exterior pattern,' the qualifier 'differentiated as...' is crucial: the prerequisite is always pattern differentiation, the cause-diagnosis and standard treatment of acute febrile illness must be led by modern medicine, and it is never a matter of applying the formula whenever there is a 'feverish cold.'

Historical development: the three acrid-cool formulas

The formula's stature comes from its role at the center of Wu's 'acrid-cool release-the-exterior' series. On the principle that 'treat the upper burner like a feather — nothing but the light will lift it,' Wu created a set of acrid-cool formulas graded by dispersing and heat-clearing strength: the light acrid-cool formula Sangju Yin (mulberry leaf and chrysanthemum foremost, the lightest doses, for early wind-warmth with cough predominant and mild fever, the 'lightest of the light'); the balanced acrid-cool formula Yinqiao Powder (this formula, for the defensive-level pattern with more marked fever); and the heavy acrid-cool formula Baihu Decoction (gypsum and anemarrhena foremost, for exuberant qi-level heat with high fever and great thirst). The three, moving from exterior to interior and light to heavy, form a clear ladder for treating the qi-level stages of warm disease.

Yinqiao Powder and Sangju Yin are both representative acrid-cool exterior-releasing formulas sharing five herbs (mint, forsythia, phragmites, platycodon, licorice), but Yinqiao adds honeysuckle, schizonepeta spike, fermented soybean, arctium, and lophatherum, giving stronger exterior-releasing and heat-clearing power and excelling at 'venting the exterior,' while Sangju Yin leans toward 'diffusing the lung and stopping cough.' Understanding the three formulas and this pair is the key to 'the same acrid-cool, yet different formulas.' Yinqiao's modifications in Wu's self-annotations are very rich (adding trichosanthes for severe thirst, adding puffball and scrophularia for neck swelling and sore throat, removing schizonepeta and soybean for nosebleed), but these belong to professional practice and are not offered here as instructions.

Active constituents: chlorogenic acid, forsythin, and antiviral exploration

In modern terms, the material basis involves many herbs' actives: honeysuckle's chlorogenic acid and luteoloside, forsythia's forsythin and forsythoside, mint's volatile oil (menthol), arctium's arctiin, and licorice's glycyrrhizic acid. Pharmacology reports anti-inflammatory, antibacterial, antiviral, antipyretic, and immunomodulatory effects for the formula and its components; experiments suggest reduced influenza-virus replication and modulation of TLR7/NF-κB and T-cell-receptor signaling, and network-pharmacology studies sketch a 'multi-component, multi-target' antiviral/immunoregulatory hypothesis.

The caveat: these are largely in-vitro, animal, and computational — mechanistic exploration. Also, the formula is mostly aromatic herbs whose actives are largely volatile oils, so tradition stresses 'do not over-boil, take as soon as the aroma emerges' — prolonged decoction loses actives, a detail that indirectly confirms its material basis lies in volatile constituents. But a mechanistic 'antiviral' effect must never be equated with proven efficacy in human disease.

Evidence: what influenza research shows (especially the 'combined formula' distinction)

A key point must be made clear about the modern evidence: many of the most-cited high-quality studies actually used a 'combination/compound of Yinqiao Powder,' not the canonical formula alone. The most famous is a randomized controlled trial in the Annals of Internal Medicine (2011, 155:217; PMID 21844547): across 11 Chinese hospitals it enrolled 410 patients with lab-confirmed H1N1 influenza, comparing oseltamivir, a maxingshigan-yinqiaosan combined formula, both together, and no treatment — all three active groups significantly shortened time to fever resolution versus control (about 34%, 37%, and 47% reductions), and the combination shortened fever time by a further ~19% versus oseltamivir alone, with good tolerability. But note: the formula was Maxing Shigan Tang combined with Yinqiao San, not Yinqiao San alone.

Additionally, a systematic review and meta-analysis (PMC7834461) assessed 'Yinqiao powder combined with Western medicine' for pneumonia, and a placebo-controlled RCT of the Korean 'Yinqiao San' (Eunkyosan) for the common cold showed symptom improvement. How to state it? First, the most-cited positive evidence largely comes from 'combined formulas' or 'combined with Western drugs,' and cannot be extrapolated to 'the canonical formula alone is effective' or 'can replace antivirals.' Second, included studies have variable methodological quality and heterogeneity. Third, 'time to fever resolution' and 'overall effectiveness' are specific outcomes. The defensible statement is that, mostly as combined formulas/combination therapy, it showed a signal of improving certain outcomes in specific settings such as influenza and pneumonia, with variable evidence quality needing careful reading — not that Yinqiao is proven to treat influenza or COVID-19.

Quality standards, patent medicines, and the Western-drug context

Honeysuckle, forsythia, mint, arctium, schizonepeta, fermented soybean, platycodon, lophatherum, phragmites, and licorice are all Chinese Pharmacopoeia (2020) materials (honeysuckle by chlorogenic acid and luteoloside, forsythia by forsythin). Yinqiao Powder is among the most common patent medicines, available as Yinqiao Jiedu pill/tablet/granule/capsule and Vitamin-C Yinqiao tablet. A special caution: compound preparations such as 'Vitamin-C Yinqiao tablet' often contain chemical-drug ingredients such as paracetamol (acetaminophen) and chlorphenamine maleate — they are not pure herbal medicine, same-named products differ markedly, and they are not interchangeable.

As contextual overlap (relationship only, not an efficacy comparison): the formula's modern research settings (influenza, common cold, early pneumonia) correspond at the Western-drug level to categories such as antivirals (e.g. oseltamivir), antipyretic-analgesics, and antihistamines — as noted, its research is often compared with or combined with oseltamivir, and some patent medicines themselves contain antipyretic/antihistamine chemicals. This points to an important safety issue: taking a Western cold medicine with the same ingredient at the same time (e.g. another paracetamol-containing product) may stack ingredients and risk overdose. This is a statement of relationship only, but for exactly that reason combination requires professional oversight and must not be self-layered.

Safety boundaries: tell wind-heat from wind-cold, and watch for ingredient stacking

Yinqiao's safety has two cores. First, the differentiation prerequisite: it is made for a 'wind-heat exterior pattern' and is cool in nature, so misuse in a wind-cold exterior pattern (marked chills, no sweat, clear nasal discharge, white coating) may 'cool and trap' the pathogen and worsen the condition — failing to tell wind-heat from wind-cold is the commonest error. Those with spleen-stomach deficiency-cold also need caution. Second, ingredient-stacking risk: as noted, 'Vitamin-C Yinqiao tablet' and the like contain chemicals such as paracetamol and chlorphenamine, and taking them with another Western cold medicine containing the same ingredient may cause overdose (paracetamol overdose carries hepatotoxicity risk).

On the boundary of use: acute febrile illness has many causes (influenza, bacterial infection, other viruses), and persistent high fever, dyspnea, poor mental state, infancy or old age, and underlying disease all call for prompt medical care to establish a diagnosis rather than self-treating with 'acrid-cool release' alone. Pregnancy and childhood use should follow medical advice. Yinqiao is an excellent model for the wisdom of 'acrid-cool release' and warm-disease differentiation, but its clinical use — especially chemical-containing compound patent medicines — requires differentiation and ingredient checking.

A checklist for reading any formula article

1. Composition and preparation: does a stated effect come from Yinqiao itself, from a maxingshigan-yinqiaosan combined formula, from a Yinqiao Jiedu preparation, or from a chemical-containing 'Vitamin-C Yinqiao tablet'? Does the patent medicine contain Western-drug ingredients such as paracetamol?
2. Pattern versus disease: has 'defensive-level / wind-heat exterior pattern' been equated directly with influenza, COVID-19, or pneumonia, and has 'differentiated as...' been dropped?
3. Evidence tier and scenario: does the positive result use 'Yinqiao alone' or 'a combined formula/combined with oseltamivir,' and is the outcome time-to-fever/overall-effectiveness or a hard endpoint?
4. Safety and interactions: does it stress telling wind-heat from wind-cold, the worsening from cool misuse in wind-cold, and the ingredient-stacking/overdose risk of chemical-containing patent medicines with Western cold drugs?
5. Dose and procedure: responsible education identifies the entity and stops short of individual dosing and modifications — for medication, consult a physician and pharmacist and check patent-medicine ingredients.

Educational and academic reference only. It does not provide a diagnosis, prescription, dosage, or treatment recommendation. This formula is cool in nature and made for a wind-heat exterior pattern; misuse in wind-cold may worsen it. Some same-named patent medicines (such as Vitamin-C Yinqiao tablet) contain chemical drugs like paracetamol and risk overdose when taken with Western cold medicines. Acute febrile illness should be promptly evaluated for diagnosis; consult a licensed physician and pharmacist for prescriptions and patent-medicine selection.