Er Zhi Wan (二至丸) — Two Solstices Pill
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Overview
Er Zhi Wan — the “Two Solstices Pill” — is from Wang Ang’s Qing-dynasty Yi Fang Ji Jie. The name “Two Solstices” reflects the traditional harvest times of its two ingredients: Nu Zhen Zi (gathered at winter solstice) and Han Lian Cao (gathered at summer solstice). It is a minimal, gentle, food-like formula for mild to moderate Liver-Kidney Yin deficiency — ideal as a constitutional support or as part of larger formulas. The lightness makes it suitable for long-term use, particularly in perimenopausal women and in patients with premature greying.
I prescribe Er Zhi Wan as part of bespoke herbal formulas from pharmaceutical-grade granules sourced from Sun Ten in Taiwan.
TCM pattern
Er Zhi Wan is prescribed for mild Liver-Kidney Yin deficiency:
- Premature greying of hair
- Hair thinning or hair loss
- Mild lower back ache, weak knees
- Mild dizziness[22], tinnitus
- Mild night sweats
- Dry mouth, mild thirst
- Tongue — red with mild scant coat
- Pulse — thin
Key herbs
- Nu Zhen Zi (Fr. Ligustri Lucidi, 9–15g) — nourishes Liver-Kidney Yin; benefits hair and eyes
- Han Lian Cao / Mo Han Lian (Hb. Ecliptae, 9–15g) — nourishes Liver-Kidney Yin; cools Blood; benefits hair
Formula actions
- Gently nourishes Liver and Kidney Yin
- Cools Blood mildly
- Benefits hair, eyes and Essence
Conditions treated
- Premature greying of hair
- Hair thinning and hair loss from Yin/Blood deficiency
- Mild perimenopausal Yin deficiency
- Post-partum hair loss with mild Yin depletion
- Mild night sweats without strong Heat
- Constitutional Yin support in long-term use
- Mild dry eyes from Liver Yin deficiency
Cautions
Mild and well-tolerated, but not appropriate for cold-deficient or Damp-Phlegm patterns — the cool nourishing herbs can dampen Spleen Yang.
For severe Yin deficiency, stronger formulas (Liu Wei Di Huang Wan, Zhi Bai Di Huang Wan) are more effective.
Always consult a qualified Chinese herbalist registered with the RCHM.
Prefer to be treated from home? Chinese herbal medicine online consultations are available throughout the UK and worldwide.
References
[22] Guo Z, Su Z, Wang Z, Luo X, Lai R. The effect of Chinese herbal medicine Banxia Baizhu Tianma Decoction for the treatment of vertebrobasilar insufficiency vertigo: A systematic review and meta-analysis of randomized controlled trials. Complement Ther Med. 2017 Apr;31:27-38. https://doi.org/10.1016/j.ctim.2017.01.004. PMID: 28434468.
