# Yokukansan (Restrain the Liver Powder)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/yokukansan-restrain-the-liver-powder
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-03-18
**Evidence Score:** 6 / 10
**Category:** Traditional Chinese Medicine
**Also Known As:** Yokukansan, Restrain the Liver Powder, Gan Mai Da Zao Tang (TCM), YKS, Liver Fire Calming Formula, Uncaria Hook Formula, Neurocalming Kampo Formula

## Overview

Yokukansan is a traditional Japanese kampo formula containing seven herbs that modulates GABA and glutamate [neurotransmitter](/ingredients/condition/cognitive) systems to reduce anxiety and agitation. The formula's primary bioactive compounds include glycyrrhizin and ginsenosides that work synergistically to calm neural hyperexcitability.

## Health Benefits

- Calms the nervous system by modulating [neurotransmitter activity](/ingredients/condition/cognitive), reducing anxiety and stress. - Enhances cognitive function by improving blood flow to the brain, supporting memory and focus. - Supports [liver health](/ingredients/condition/detox) by promoting detoxification processes, aiding in toxin elimination. - Reduces irritability by balancing neurotransmitter levels, leading to a more stable mood. - Improves sleep quality by regulating [melatonin production](/ingredients/condition/sleep), ensuring restful nights. - Alleviates menopausal symptoms by modulating hormone levels, providing relief from mood swings. - Supports [digestive health](/ingredients/condition/gut-health) by reducing gut [inflammation](/ingredients/condition/inflammation), promoting a balanced microbiome.

## Mechanism of Action

Yokukansan modulates [neurotransmitter](/ingredients/condition/cognitive) balance by enhancing GABAergic inhibition while reducing glutamate excitotoxicity in the brain. Key compounds like glycyrrhizin from licorice and ginsenosides from ginseng cross the blood-brain barrier to regulate calcium channels and reduce neuronal hyperexcitability. The formula also influences serotonin and [dopamine pathway](/ingredients/condition/mood)s through interactions with 5-HT1A receptors and monoamine transporters.

## Clinical Summary

Multiple randomized controlled trials have demonstrated yokukansan's efficacy in reducing behavioral symptoms in dementia patients, with studies showing 30-50% reduction in agitation scores over 4-12 week periods. A systematic review of 12 studies involving over 800 participants found significant improvements in anxiety and [sleep quality](/ingredients/condition/sleep) with typical doses of 7.5g daily. However, most high-quality research focuses on elderly populations with dementia, and evidence for healthy adults remains limited to smaller preliminary studies.

## Nutritional Profile

Yokukansan (抑肝散) is a traditional Kampo/Chinese herbal formula, not a food, so conventional macronutrient profiling (calories, fat, carbohydrates, protein) is not applicable in standard dietary terms. Its therapeutic value derives entirely from its bioactive compounds across its seven constituent herbs. Typical formulation (per daily dose, ~7.5 g of dried extract granules or ~20–25 g of crude herb decoction): **Constituent Herbs & Key Bioactive Compounds:** 1. **Atractylodes lancea rhizome (Sōjutsu/Cangzhu, ~4.0 g crude):** Atractylodin (~0.3–0.8 mg/g), atractylone, beta-eudesmol; sesquiterpenoids with [anti-inflammatory](/ingredients/condition/inflammation) and gastrointestinal-modulating activity. 2. **Poria cocos (Bukuryō/Fuling, ~4.0 g crude):** Pachymic acid (~0.5–2.0 mg/g), triterpenoids (dehydropachymic acid, tumulosic acid), polysaccharides (beta-glucans, ~2–5% w/w); supports mild diuretic and [immunomodulatory](/ingredients/condition/immune-support) effects. Provides trace potassium and magnesium. 3. **Cnidium officinale rhizome (Senkyū/Chuanxiong, ~3.0 g crude):** Ligustilide (~5–15 mg/g, primary phthalide), senkyunolide A (~1–3 mg/g), ferulic acid (~0.5–1.5 mg/g); these phthalides and phenolic acids promote cerebral vasodilation and exhibit [antioxidant](/ingredients/condition/antioxidant) properties. Ferulic acid bioavailability is relatively high (~40–60% oral absorption). 4. **Angelica acutiloba root (Tōki/Danggui, ~3.0 g crude):** Z-ligustilide (~3–10 mg/g), ferulic acid (~0.5–2.0 mg/g), polysaccharides (angelica polysaccharides ~3–5% w/w), vitamin B12 (trace, ~0.05–0.2 µg/g), folic acid (trace), iron (trace, ~0.1–0.5 mg/g crude herb). Supports hematopoiesis. Ferulic acid shows good oral bioavailability. 5. **Bupleurum falcatum root (Saiko/Chaihu, ~2.0 g crude):** Saikosaponins a, c, and d (~5–15 mg/g total); triterpenoid saponins with anti-inflammatory, [hepatoprotective](/ingredients/condition/detox), and corticosteroid-modulating activity. Saikosaponin a is converted by gut microbiota, with bioavailability estimated at ~10–20%. 6. **Glycyrrhiza uralensis root (Kanzō/Gancao, ~1.5 g crude):** Glycyrrhizin (~20–40 mg/g), glycyrrhetinic acid (metabolite), liquiritigenin (~1–3 mg/g), isoliquiritigenin (~0.5–2 mg/g); flavonoids with estrogenic, anti-inflammatory, and GABA-A receptor-modulating effects. Glycyrrhizin oral bioavailability is low (~1–5%) but is hydrolyzed to glycyrrhetinic acid by intestinal bacteria with much higher systemic exposure. Contains trace minerals including manganese and zinc. 7. **Uncaria rhynchophylla hook (Chōtōkō/Gouteng, ~3.0 g crude):** Geissoschizine methyl ether (GM, ~0.5–2.0 mg/g) — a key indole alkaloid acting as a partial agonist at [serotonin](/ingredients/condition/mood) 5-HT1A receptors and antagonist at 5-HT2A, 5-HT2C, and dopamine D2 receptors; rhynchophylline (~2–6 mg/g), isorhynchophylline (~1–4 mg/g), hirsutine (~0.5–2 mg/g); oxindole and indole alkaloids with [neuroprotective](/ingredients/condition/cognitive), anti-glutamatergic, and calcium channel-blocking activity. GM bioavailability is moderate and considered the primary active constituent for neuropsychiatric effects. **Mineral & Micronutrient Traces (aggregate, approximate per daily dose):** Potassium: ~15–40 mg; Calcium: ~10–30 mg; Magnesium: ~5–15 mg; Iron: ~1–3 mg; Zinc: ~0.2–0.8 mg; Manganese: ~0.3–1.0 mg. **Fiber/Polysaccharides:** Total soluble polysaccharides from Poria, Angelica, and Atractylodes contribute approximately 200–500 mg per daily dose, with [prebiotic](/ingredients/condition/gut-health)-like effects on gut microbiota. **Bioavailability Notes:** Many active compounds (saikosaponins, glycyrrhizin, oxindole alkaloids) undergo extensive first-pass hepatic [metabolism](/ingredients/condition/weight-management) and gut microbial biotransformation, significantly altering their systemic bioactive profiles. Geissoschizine methyl ether and ferulic acid demonstrate relatively favorable oral bioavailability. Phthalides (ligustilide) are volatile and heat-labile, with bioavailability varying significantly depending on preparation method (decoction vs. granule extract). Co-administration of glycyrrhizin may enhance bioavailability of other constituents through P-glycoprotein and CYP450 modulation.

## Dosage & Preparation

Dosage should be prescribed by a Kampo practitioner. Consult a healthcare provider before use.

## Safety & Drug Interactions

Yokukansan is generally well-tolerated but can cause pseudoaldosteronism due to glycyrrhizin content, leading to elevated [blood pressure](/ingredients/condition/heart-health) and hypokalemia with prolonged use. The formula may interact with digoxin, diuretics, and corticosteroids due to licorice root components. Contraindications include severe liver disease, pregnancy, and breastfeeding due to insufficient safety data. Monitoring of blood pressure and electrolytes is recommended during extended use exceeding 8 weeks.

## Scientific Research

Research, including randomized controlled trials, indicates that Yokukansan may help reduce symptoms of anxiety and agitation, particularly in dementia patients. More studies are needed to explore its full potential.

## Historical & Cultural Context

Yokukansan has been used in Kampo medicine for centuries to address [mental health](/ingredients/condition/mood) issues. It exemplifies the integration of traditional Chinese herbal medicine into Japanese therapeutic contexts.

## Synergistic Combinations

Licorice root, Uncaria, Peony root, Bupleurum

## Frequently Asked Questions

### How long does yokukansan take to work for anxiety?

Clinical studies show yokukansan typically begins reducing anxiety symptoms within 2-4 weeks of daily use. Most patients experience significant improvement by 8 weeks when taking the standard dose of 7.5g daily divided into three doses.

### What is the recommended yokukansan dosage for adults?

The standard adult dosage is 7.5g of yokukansan extract powder daily, divided into three doses of 2.5g each before meals. This dosage has been validated in clinical trials and provides therapeutic levels of active compounds like glycyrrhizin.

### Can yokukansan cause high blood pressure?

Yes, yokukansan can elevate blood pressure due to glycyrrhizin in licorice root, which can cause sodium retention and potassium loss. This pseudoaldosteronism effect is dose-dependent and more likely with prolonged use exceeding 8 weeks.

### Is yokukansan safe to take with antidepressants?

Yokukansan may interact with antidepressants through serotonin pathway modulation, potentially affecting drug metabolism. Consult a healthcare provider before combining with SSRIs, as the formula may enhance or interfere with antidepressant effects.

### What are the main herbs in yokukansan formula?

Yokukansan contains seven herbs: Atractylodes lancea, Poria cocos, Cnidium officinale, Angelica acutiloba, Bupleurum falcatum, Glycyrrhiza uralensis, and Uncaria hook. Each herb contributes specific bioactive compounds that work synergistically for neurological benefits.

### Is yokukansan safe during pregnancy and breastfeeding?

Yokukansan has not been extensively studied in pregnant or breastfeeding women, and traditional use does not necessarily establish safety in these populations. It is recommended to consult with a healthcare provider before using yokukansan during pregnancy or while breastfeeding, as some herbs in the formula may affect fetal development or pass into breast milk. Pregnant women should exercise particular caution with any herbal supplement without clear safety data.

### What does clinical research show about yokukansan's effectiveness for anxiety and insomnia?

Several Japanese and Asian clinical studies have demonstrated yokukansan's efficacy in reducing anxiety, irritability, and sleep disturbances, with improvements typically observed within 2–4 weeks of consistent use. A randomized controlled trial showed benefit for behavioral symptoms in dementia patients, and neuroimaging studies suggest it modulates neurotransmitter activity in regions associated with emotional regulation. However, most high-quality evidence comes from Asian populations, and larger Western clinical trials are needed to fully establish its therapeutic profile.

### Who should avoid yokukansan, and are there specific populations at higher risk for side effects?

Yokukansan should be used cautiously in individuals with severe kidney or liver disease, as the herbs require hepatic metabolism and renal clearance. Elderly individuals and those taking multiple medications should consult a healthcare provider before use, as they may have increased sensitivity to herbal constituents or greater risk of drug interactions. Pregnant women, nursing mothers, and children under 12 should generally avoid yokukansan unless specifically recommended by a qualified practitioner.

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