Kamishoyosan is a 10-herb Kampo formula that evolved from the classical Chinese formula Xiaoyaosan, with the addition of gardenia and moutan to address heat and emotional restlessness. It has been a cornerstone of Japanese integrative gynecology for over 400 years and is today one of the most commonly prescribed Kampo formulas in Japanese hospital and clinic settings. Unlike single-herb supplements, it works as a synergistic blend where each botanical contributes a specific role to the overall effect.

The formula targets the interplay between emotional stress, liver function, and hormonal balance — concepts central to East Asian medicine that modern research is beginning to map onto Western physiology. Key herbs like bupleurum and peony appear to help calm the nervous system and regulate estrogen-related signaling, while gardenia and moutan address inflammation and heat symptoms like flushing. Poria and atractylodes support digestive and adrenal function, helping the body recover its equilibrium during hormonally turbulent periods.

In Japan, Kamishoyosan is most commonly dispensed as a granule powder (TJ-24 by Tsumura) that dissolves in warm water, as it is officially approved and reimbursed under Japan's national health insurance system. Tablets and capsules are available internationally. Traditional decoction (simmering the raw herbs) is still used by some practitioners for custom dosing. Granules and decoctions are considered most bioavailable by Kampo practitioners.

• PMS and premenstrual mood symptoms
• Menopause symptoms (hot flashes, night sweats)
• Irritability and emotional tension
• Anxiety and stress
• Irregular periods
• Sleep disturbances related to hormonal changes
• Mild depression tied to hormonal shifts
• Headaches linked to menstrual cycle
• Autonomic nervous system imbalance (palpitations, dizziness)
• Climacteric disorder

• Recurrence of PMS severity with continuous use during luteal phase

Kamishoyosan is a multi-herb formula not found in food. To support the same goals — hormonal balance, stress resilience, and nervous system calm — focus on these dietary patterns and foods: (1) Phytoestrogen-rich foods like flaxseed, edamame, and fermented soy (miso, tempeh) may gently support estrogen balance during perimenopause. (2) Cruciferous vegetables (broccoli, cauliflower, Brussels sprouts) support healthy estrogen metabolism via the liver. (3) Magnesium-rich foods — pumpkin seeds, dark leafy greens, dark chocolate — help calm the nervous system and reduce PMS severity. (4) Omega-3 fatty acids from fatty fish, walnuts, and chia seeds reduce the inflammatory signaling that worsens hot flashes and mood symptoms. (5) Avoid excess caffeine and alcohol, which worsen hot flashes, disrupt sleep, and amplify anxiety — working directly against what Kamishoyosan is trying to achieve.

• Mild stomach upset or nausea (especially when taken without food)
• Loose stools or diarrhea
• Skin rash or allergic reaction (uncommon)
• Elevated liver enzymes with prolonged use (rare — monitor with long-term use)
• Pseudo-aldosteronism from licorice component (rare, mainly with high-dose or very long-term use — symptoms include water retention and elevated blood pressure)

• Recommended daily: Standard Japanese clinical dose: 7.5 g of granule preparation (TJ-24) daily, divided into 2–3 doses. This is equivalent to approximately 2.5 g per dose, three times daily. Western capsule formats vary by manufacturer — follow label guidance, typically 3–6 capsules daily.
• Best time of day: Traditionally taken 30 minutes before meals (the classic Kampo timing). If this causes stomach sensitivity, taking immediately after meals is acceptable.
• With or without food: Ideally before meals for optimal absorption per Kampo tradition, but taking with food reduces the chance of nausea for those with sensitive stomachs.
• Time to effect: Mood and irritability improvements are often noticed within 2–4 weeks. Hot flash and physical menopausal symptoms may take 4–8 weeks for meaningful change. Full benefit typically assessed at 8–12 weeks.
• How long to take it: Short-term use for acute PMS symptoms: use during the luteal phase (10–14 days before period) each cycle. For menopausal symptoms: continuous use for 3–6 months is typical in clinical trials. Long-term use beyond 6 months should include periodic liver function monitoring. Reassess every 3 months with a practitioner.