Q2: Which modern conditions is Liu Yi San indicated for?

It is frequently used for urinary tract infections, heatstroke, heat stress reactions, and mild urinary tract inflammation, where the pattern diagnosis is internal accumulation of summer-heat dampness or downward infusion of damp-heat.

Q3: Is Liu Yi San suitable for summer heatstroke management?

For thirst and irritability, fever with profuse sweating, short dark-yellow urine, and dizziness and fatigue after exposure to high temperatures, Liu Yi San may be used as an adjunct treatment when the pattern corresponds to internal accumulation of summer-heat dampness. It cannot replace emergency medical intervention for severe heatstroke.

Heat-Clearing Formulas

六一散 · Liù Yī Sàn

Liu Yi San

A simple classical powder of talcum and licorice (6:1) for summer-heat with dampness, presenting with fever, thirst, irritability and scanty urine in hot weather.

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Last reviewed August 2026

Formula CategoryHeat-Clearing Formulas

Primary PatternSummer Heat

Primary FunctionClear summer-heat, drain dampness

Primary Therapeutic PrincipleClear summer-heat and promote urination to drain dampness

Main HerbsTalcum · Licorice Root

Classical SourceShang Han Zhi Ge Fang / attributed to Liu Wansu tradition

Why This Formula?

Traditionally selected as a light, foundational formula for summer-heat with damp and scanty urine — often combined or used early before stronger Qi-tonifying summer formulas are needed.

Overview

What Is Liu Yi San?

1. Ancient Origins

Liu Yi San (六一散), or Six-to-One Powder, is a classical Jin-dynasty formula from Liu Wansu’s Huangdi Suwen Xuanming Lun Fang (Formulas from the Discussion Illuminating the Yellow Emperor’s Basic Questions). It belongs to the category of formulas that clear Summer-Heat and resolve Dampness.

This simple yet effective formula addresses Summer-Heat combined with internal Dampness. Typical signs include fever, thirst, irritability or restlessness, scanty dark urine, and sometimes diarrhea or urinary difficulty during hot weather.

Composed of Hua Shi (talcum) and Gan Cao (licorice) in a classic 6:1 ratio, Liu Yi San clears Summer-Heat, promotes urination to drain Damp-Heat, protects body fluids, and is also applied externally for prickly heat, making it a foundational remedy for summer-related Heat-Damp patterns.

2. Urological Conditions

Liu Yi San is a very popular choice for treating various urinary tract issues. If you are dealing with symptoms like needing to go frequently, an urgent need to pee, pain during urination, or urine that is dark and concentrated, this formula can help.

UTIs and Inflammation: It is commonly used for conditions like cystitis (bladder inflammation) or urethritis. By clearing out "damp-heat," it reduces the internal inflammation and eases the burning sensation.
Faster Recovery: Research shows that when you combine Liu Yi San with standard antibiotics for a UTI, the symptoms clear up faster and the overall treatment is more effective.
Kidney Support: In the early stages of more serious issues like acute pyelonephritis (a type of kidney infection), it can be used as a supporting formula to help flush out the internal "heat" and support the body’s healing process.

3. Skin Conditions

In the world of dermatology, this formula is a go-to for clearing up "wet" or "hot" skin rashes like eczema and prickly heat.

Eczema Relief: Eczema is often seen as a buildup of internal dampness and heat that "leaks" to the skin. Liu Yi San clears this heat from the inside out, which helps reduce the redness, swelling, and intense itching.
Prickly Heat: This is the classic remedy for heat rash during the summer. It cools the skin and stops the itch.
Topical Use: One of the best ways to use it for rashes is to apply the powder directly to the skin. It helps keep the area dry and provides almost instant relief from the discomfort of heat rash.

4. Summer Heatstroke and Summer-Heat Conditions

When the weather gets muggy and hot, your body can trap "summer-heat dampness," leading to fever, constant thirst, and trouble urinating. Liu Yi San is a summer essential for these situations.

Heatstroke Prevention: During the peak of summer, taking a small dose can help prevent "summer-heat colds" caused by the humid weather.
Post-Exercise Recovery: If you’ve been working out or working outside in high temperatures, drinking Liu Yi San (either as a tea or dissolved granules) is a great way to cool your core temperature and maintain your physical comfort.
Expelling Toxins: It allows the "summer-heat" to be safely expelled from the body, helping you feel refreshed rather than weighed down by the humidity.

How It Works

Herb Composition (Sovereign / Minister / Assistant / Envoy)

1. Sovereign Herb: Hua Shi (Talcum)

Hua Shi is the "leader" of this formula. It has a sweet, mild flavor and a cooling nature, targeting the Bladder, Lungs, and Stomach.

How it works: Its texture is naturally smooth and "slippery." It is famous for clearing heat and promoting urination.
The Main Job: It acts as a vanguard, flushing out "damp-heat" (which you can think of as inflammation or infection in the lower body) through the urine.
Relief: By guiding these toxins out, it effectively relieves uncomfortable symptoms like painful, urgent, or dribbling urination. It clears the path so your body can get rid of the discomfort smoothly.

2. Minister Herb: Gan Cao (Licorice Root)

Gan Cao is the "harmonizer" or peacekeeper of the formula. It has a sweet flavor and a neutral, balanced nature.

The Balancer: It serves to mellow out the formula. Because Hua Shi is very cold, Gan Cao makes sure it doesn't become too harsh on your digestive system (the middle burner).
Protecting Energy: It boosts your Spleen and Qi (energy). This is important because while the first herb is busy flushing things out, Gan Cao ensures that your body doesn't lose too much energy or become too weak in the process.
A Gentle Touch: It acts as a buffer, making the entire formula more balanced so it can do its job without causing unwanted side effects.

3. Note on Assistant and Envoy Roles

Even though Liu Yi San only contains two ingredients, they follow the classic four-part strategy of traditional formulas:

Coordinated Teamwork: Hua Shi handles the heavy lifting of clearing heat, while Gan Cao provides the necessary support and balance.
The "Six to One" Ratio: The name Liu Yi San actually refers to the specific 6:1 ratio of Hua Shi to Gan Cao.
Precision: This exact proportion is the "secret sauce." It ensures the formula is strong enough to drain dampness and clear heat effectively, but gentle enough that it won't overwhelm your body’s natural balance.

Symptoms Traditionally Associated

Clinical Presentation in TCM

1. Pathomechanism and Syndromes

The main issue Liu Yi San tackles is the buildup of "damp-heat" inside the body. You can think of damp-heat like trapped, sticky humidity combined with internal heat.

Bladder Issues: When this damp-heat settles in the lower part of your body (the "lower burner"), it messes with your bladder. This leads to that annoying feeling of needing to go all the time, pain when you pee, or a flow that feels blocked.
Skin Problems: Sometimes this heat "simmers" just under the skin. This is what causes itchy eczema, prickly heat rashes, and other skin flare-ups.
The Summer Factor: These symptoms are most common during the hot, humid summer months. When the weather is muggy, your body is much more likely to trap this "summer-heat dampness."

2. Summer-Heat Clearing and Dampness-Draining Actions

The primary goal of Liu Yi San is to cool you down and "drain" the excess moisture.

The Internal Flush: Hua Shi clears the heat and encourages urination, while Gan Cao keeps the formula balanced. Together, they act like a cooling flush for your system.
Restoring Flow: It specifically targets dark, concentrated, or painful urination, helping to restore a normal, comfortable flow.
Internal Skin Care: By regulating the damp-heat from the inside, it helps clear up the "steaming" effect that causes rashes on the outside.

3. Indications

Liu Yi San is the go-to formula for a variety of heat-related conditions, especially in the summer:

Summer-Heat Sickness: If you have a fever, feel constantly thirsty, and are having trouble peeing during hot and rainy weather, this formula helps clear that "summer-heat."
Urinary Discomfort: It is highly effective for what we call "Lin" patterns—which feel a lot like a UTI (urinary tract infection)—including frequency, urgency, and dark yellow urine.
Heat Rashes and Eczema: It is great for clearing up prickly heat or eczema caused by that trapped, swampy heat in the skin.

Essentially, it acts as a "key" to unlock and release the heat and dampness that cause these uncomfortable blockages.

Formula Analysis

The Mechanism in Classical Theory

1. Hua Shi: Clearing Heat and Promoting Urination

Hua Shi (Talcum) is cold by nature and has a very smooth, "gliding" texture. This allows it to work specifically on the lower part of your body and the bladder.

Flushing the System: It is an expert at clearing out "damp-heat" by directing it out of the body through your urine.
A Natural Lubricant: Because of its slippery quality, it essentially "greases the wheels" of the urinary tract. This reduces the irritation caused by infection or inflammation.
Pain Relief: By smoothing out the flow, it helps stop the stinging, dribbling, and painful sensations that come with urinary issues.

In this formula, Hua Shi is the heavy lifter that ensures the toxins have a clear, smooth exit strategy.

2. Gan Cao: Harmonising the Formula

Gan Cao (Licorice Root) is the ultimate balancer in traditional formulas. It is sweet and neutral, making it perfect for keeping the other ingredients in check.

The Safety Buffer: Since Hua Shi is very cold, Gan Cao acts as a shield to prevent that coldness from upsetting your stomach or digestive energy (Spleen-Stomach Yang Qi).
Steady Progress: It coordinates with the other herbs to make sure the "flushing" action is balanced and sustainable, rather than too harsh or sudden.
The Dedicated Assistant: It works behind the scenes to make sure the formula is both effective at draining dampness and safe for your body to process long-term.

3. Compositional Characteristics

The most impressive thing about Liu Yi San is how simple and focused it is. Even though it only uses two ingredients, it is incredibly effective at clearing out internal damp-heat.

The Golden Ratio: The formula uses a precise 6:1 ratio of Hua Shi to Gan Cao.
Perfect Balance: This specific proportion ensures that the cooling and "draining" power of the Hua Shi is strong enough to work, while the Gan Cao is just enough to keep the formula gentle.
Less is More: This "minimalist" approach shows the beauty of herbal science—targeting a specific problem with exactly what is needed, leading to reliable results without unnecessary complexity.

How This Formula Compares

Clinical Comparison Table

Compare	Liu Yi San	Xiang Ru Yin	Qing Shu Yi Qi Tang	Wu Ling San
Primary Function	Clear summer-heat, drain dampness	Release exterior, dispel summer-damp, harmonise the Middle	Clear summer-heat, benefit Qi, generate fluids	Promote urination, drain Dampness, warm Yang
Formula Category	Heat-Clearing Formulas	Exterior-Releasing Formulas	Qi-Tonifying Formulas	Dampness-Draining Formulas
Typical TCM Pattern	Summer Heat	Summer Heat	Summer Heat	Dampness
Main Conditions	Fever, Dry Mouth & Throat, Frequent Urination, Fatigue & Low Energy	Fever, Cold Limbs, Diarrhea, Abdominal Pain, Nausea	Fatigue & Low Energy, Fever, Dry Mouth & Throat, Poor Appetite, Spontaneous Sweating	Edema, Frequent Urination, Damp Constitution
Main Herbs	Talcum · Licorice Root	Mosla · White Hyacinth Bean · Magnolia Bark	American Ginseng · Dendrobium · Ophiopogon Tuber · Coptis Rhizome · Lophatherum · Lotus Stem · Anemarrhena Rhizome · Licorice Root · Non-glutinous Rice · Watermelon Rind	Alisma Rhizome · Poria / Hoelen · Polyporus · White Atractylodes Rhizome · Cinnamon Twig
Classical Source	Shang Han Zhi Ge Fang / attributed to Liu Wansu tradition	Tai Ping Hui Min He Ji Ju Fang (Song dynasty)	Wen Re Jing Wei (Wang Mengying, Qing dynasty) / Li Dongyuan tradition variants	Shang Han Lun (Zhang Zhongjing, Eastern Han)

How to tell them apart

Liu Yi San is the basic summer-heat and damp clearing powder. Xiang Ru Yin releases exterior summer-damp with chills. Qing Shu Yi Qi Tang tonifies Qi while clearing summer-heat for deficiency presentations. Wu Ling San drains damp and promotes urination without a summer-heat focus.

For educational reference only, based on traditional pattern differentiation — not a substitute for professional advice.

Clinical Modifications

Clinical Modifications for Liu Yi San

1. Severe Damp-Heat

If the "damp-heat" symptoms are especially strong—for example, if you have a very bitter taste in your mouth and a thick, yellow, greasy coating on your tongue—we add stronger "drying" herbs to the mix:

Huang Lian (Coptis Rhizome) and Huang Bo (Phellodendron Bark): These are powerful herbs for clearing heat and drying out dampness.
Why add them: They significantly boost the formula's ability to kill off internal inflammation. This is perfect for when the stinging and urgency during urination are very intense, indicating a heavy buildup of toxins in the lower body.

2. Pronounced Inhibited Urination

When the biggest problem is that you simply cannot pee, or the flow is extremely blocked and difficult, we add herbs that specialize in "unblocking the pipes":

Che Qian Zi (Plantain Seed) and Qu Mai (Dianthus): These herbs are experts at promoting urination and unblocking "strangury" (that painful, stuck feeling).
How they work: They reinforce Liu Yi San by forcing the urine to flow more freely. This helps flush the damp-heat out of the lower body much faster, which is essential if you feel like your bladder is completely suppressed or won't empty.

3. Concurrent Summer-Heat

If you are dealing with summer-heat along with the dampness—meaning you have a high fever and feel incredibly thirsty—we add "fire-purging" herbs to cool your core:

Shi Gao (Gypsum) and Zhi Mu (Anemarrhena Rhizome): These two are a famous pair for draining internal fire and generating fluids.
The Result: They help the formula cool you down more effectively while also relieving that intense thirst. This is the best approach during the peak of summer when the heat is just as much of a problem as the humidity, ensuring your body stays hydrated and cool.

Modern Research

What the Science Suggests

Liu Yi San (Six-to-One Powder) is a simple yet effective formula in Traditional Chinese Medicine consisting of Hua Shi and Gan Cao in a 6:1 ratio.

It clears heat, promotes urination, and to promote urination while protecting fluids and the spleen. The formula is commonly used for summer-heat dampness syndromes, painful urination, difficult urination, and urinary issues such as urinary stones or small intestine heat pouring into the bladder, often presenting with a red tongue. By guiding heat and fluids downward through urine with the help of cool water properties, Liu Yi San is frequently combined with Xiao Yao San or other formulas to resolve damp-heat accumulation and restore normal water metabolism.

1. Pharmacological Research

Modern science has taken a closer look at the two ingredients in Liu Yi San to see how they work on a chemical level. Here is what the research shows:

Hua Shi: Studies have found that this mineral contains magnesium silicate and other compounds that act as a natural diuretic and antibacterial agent. It helps increase urine output and keeps the urinary system moving, which is key for preventing and treating infections.
Gan Cao: This herb contains active compounds like glycyrrhizin and liquiritin. These have been proven to have anti-inflammatory, anti-allergic, and immune-boosting properties.

When you put them together, they create a synergistic effect that clears out dampness, fights inflammation, and cools the body, providing a solid scientific foundation for why this formula works so well.

2. Clinical Efficacy Observations

Doctors have conducted many studies to see how Liu Yi San performs in real-life medical cases. The results show it is a very reliable formula:

Proven Success: Research shows it works very well for treating bladder infections (cystitis), urinary tract inflammation (urethritis), and skin issues like eczema.
A Perfect Partner: When used alongside Western medications, Liu Yi San helps improve cure rates and reduces the chance of the problem coming back. Patients also reported fewer side effects compared to using only Western drugs.
Summer Protection: It is also effective at preventing "summer-heat colds" and boosting the body’s natural resistance against the draining effects of hot, humid weather.

3. Dosage Form Improvement Research

As medical technology advances, researchers are finding ways to make Liu Yi San even easier to use without losing its traditional benefits:

Modern Formats: While concentrated granules are common, you can now find this formula in capsules and tablets.
Better Quality: These new forms keep the ingredients stable and effective for a longer time and are much more convenient to take if you are traveling or at work.
Gentle on the Body: Capsules, in particular, do a great job of protecting the medicinal ingredients and reducing stomach irritation, making it easier for patients to stick to their treatment plan.

Summary

Liu Yi San is a classic formula with a long history and a wealth of clinical experience behind it. By looking at its origins, its simple yet effective ingredients like Hua Shi and Gan Cao, and the modern research backing it up, we can see why it remains a "go-to" remedy for damp-heat issues.

When using traditional formulas, it is always important to follow professional guidance and ensure the treatment matches your specific body pattern for the safest and best results.

Safety

Safety Considerations

1. Contraindications & Pregnancy Caution

Liu Yi San is cold/cooling and indicated for damp‑heat; avoid in deficiency‑cold patterns (e.g., spleen‑stomach deficiency‑cold, kidney yang insufficiency) as it may worsen cold signs (abdominal pain, diarrhea, cold limbs). Use with caution in pregnancy—weigh risks vs. benefits under physician guidance before treating damp‑heat in pregnant patients.

2. Dietary Restrictions & Clinical Practice

While taking Liu Yi San, avoid spicy, greasy, and irritating foods and alcohol that aggravate damp‑heat; follow a light diet rich in vegetables and fruit to support recovery. Ensure accurate pattern differentiation before use and seek medical review if symptoms change or fail to improve.

Available Products

Where to Get It

HJMEDICAL Nong's Liu Yi San (Six-to-One Powder) 5:1 Concentrated Granules $35.20

HJMEDICAL Hoi Tin Ba Zheng San (Eight-Herb Powder for Rectification) 5:1 Concentrated Granules $20.76

HJMEDICAL Nong's Ba Zheng San (Eight Rectifications Powder) 5:1 Concentrated Granules $44.83

Nong's Gan Lu Xiao Du Dan Extract Capsules

HJMEDICAL Nong's Gan Lu Xiao Du Dan (Sweet Dew Special Pill) 5:1 Concentrated Granules $119.73

FAQ

Questions About Liu Yi San

Q1: What are the actions of Liu Yi San?

Liu Yi San has the actions of clearing Summer-Heat and resolving Dampness. It is a simple yet classic formula that clears Heat while promoting urination to drain Dampness, making it especially useful for Summer-Heat patterns complicated by Dampness.

Q2: Which modern diseases is Liu Yi San suited to?

Modern TCM clinical practice commonly applies it to individuals whose pattern differentiation falls within Summer-Heat with Dampness, including heat stroke or summer heat syndromes with fever and thirst, mild urinary discomfort or scanty dark urine from Damp-Heat, acute summer diarrhea or gastroenteritis of Damp-Heat type, and externally for prickly heat (miliaria).

Q3: Is Liu Yi San suitable for improving fever, thirst, irritability, and scanty dark urine in summer?

For presentations of fever or body heat, thirst, irritability, fatigue, scanty dark urine, difficult urination, or summer diarrhea — in those whose pattern differentiation confirms Summer-Heat complicated by Dampness — TCM commonly applies Liu Yi San as an adjunct. It cannot replace standard medical treatment.

Q4: Who should not take Liu Yi San?

Those with Spleen-Stomach deficiency Cold (loose stools, poor appetite, cold limbs without Heat signs), Yin deficiency without Dampness, copious clear urination, or marked weakness are generally not suitable. Caution is advised in pregnancy. Use should be assessed by a qualified TCM physician.

Q5: Why is the formula named “Six-to-One Powder”?

The name reflects the classical ratio of its two ingredients: six parts Hua Shi (Talcum) to one part Gan Cao (Licorice). This simple yet precise proportion allows Hua Shi to clear Heat and drain Dampness while Gan Cao moderates its cold nature and harmonizes the Middle.

Q6: Can Liu Yi San be used both internally and externally?

Yes. Internally it clears Summer-Heat and resolves Dampness for systemic symptoms such as fever, thirst, and urinary or digestive issues. Externally, the powder is traditionally applied to the skin to soothe and dry prickly heat (heat rash) and certain damp skin eruptions.

Q7: What are the main ingredients of Liu Yi San?

The classical formula consists of only two herbs in a 6:1 ratio: Hua Shi (Talcum) as the chief to clear Summer-Heat, drain Damp-Heat, and promote urination, and Gan Cao (Licorice) to harmonize the formula, mildly clear Heat, protect the Middle Jiao, and moderate the cold, descending nature of Hua Shi.

Q8: Is Liu Yi San suitable for long-term use?

No. It is intended for short-term use during acute Summer-Heat with Dampness presentations. Once the Heat and Dampness symptoms resolve, the formula should be stopped. Prolonged use of the cold, draining Hua Shi can injure the Spleen and Stomach or deplete fluids if there is no clear Damp-Heat.

Q9: How does Liu Yi San clear Summer-Heat while also resolving Dampness?

Hua Shi is cold, bland, and slippery: it clears Heat from the Triple Burner and opens the urinary passages so that both Heat and Dampness can be drained downward through the urine. Gan Cao protects the Middle and prevents excessive cooling, allowing the formula to clear Summer-Heat without overly damaging Qi or fluids when Dampness is present.

Q10: What lifestyle advice supports the use of Liu Yi San?

Avoiding prolonged exposure to intense heat and humidity, drinking adequate fluids, choosing light and easily digestible foods, and resting in a cool environment help support the formula’s Summer-Heat-clearing and Dampness-resolving effects. Professional medical evaluation remains essential for severe heat-related illness or persistent urinary symptoms.

FAQ

General Questions

How do I choose the right formula?

TCM formulas are traditionally selected according to individual pattern differentiation rather than by symptom alone. If you're not sure which formula fits your presentation, take our AI Assessment below for a personalized starting point, then confirm with a qualified TCM practitioner.

What are concentrated herbal granules?

Concentrated herbal granules are made by decocting raw herbs, then extracting and concentrating the resulting liquid into a fine granule or powder form. This preserves the same active compounds as a traditional decoction while making the herbs far easier to store, measure, and prepare.

How should I take these products?

Dissolve the recommended amount of granules in hot water, stir until fully dissolved, and drink while warm — following the dosage and frequency advised by your TCM practitioner or as stated on the product packaging.

Are concentrated herbal granules equivalent to traditional decoctions?

Concentrated granules are produced from the same herbs and processed to retain their active compounds, so they are traditionally regarded as a convenient alternative to decoctions rather than a different remedy. Some practitioners note subtle differences in strength or absorption between the two forms, so your TCM practitioner may adjust dosage accordingly.

Are your products authentic?

Yes. HJMEDICAL sources its concentrated granules exclusively from established, reputable manufacturers such as Nong's and Hoi Tin, both long-standing names in the TCM granules industry, with GMP compliance stated directly on their packaging.

Are HJMEDICAL products manufactured under GMP standards?

HJMEDICAL sources its concentrated granules from established, reputable manufacturers such as Nong's and Hoi Tin, both long-standing names in the TCM granules industry. GMP compliance for these products is stated directly on their packaging.

Do you ship internationally?

Yes — we ship worldwide! Every order goes out via Hong Kong Post, and your exact shipping cost and estimated delivery time for your address are calculated and shown right at checkout, so there are never any surprises. We also offer free shipping once your order reaches our free-shipping threshold, so it's easy to stock up on your favorite formulas and save.

Can I take more than one formula at the same time?

Some formulas are traditionally combined, while others overlap or counteract each other. We recommend checking with a qualified TCM practitioner before combining formulas, especially if you are already taking other medication.

Are these products suitable during pregnancy or breastfeeding?

Some TCM formulas are not suitable during pregnancy or breastfeeding. Please consult a qualified TCM practitioner or your doctor before use if you are pregnant, trying to conceive, or nursing.

Do these products replace medical treatment?

No. These products are traditional herbal supplements intended to support wellbeing according to TCM principles — they are not a replacement for professional medical diagnosis or treatment. Please consult a qualified TCM practitioner or licensed healthcare provider before starting, stopping, or combining any treatment, especially if you have a chronic condition.

Medical Disclaimer

For general TCM education only — not medical advice. Consult a qualified TCM practitioner or licensed healthcare provider before use, especially if pregnant, nursing, on medication, or managing a chronic condition.

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