Source 出处 · Jingyue Quanshu · Doses are not given here: they are set by a licensed practitioner for the individual.
Safety. You Gui Wan is the other half of the pair and comes from the same Ming-dynasty source, Jingyue Quanshu. Where Zuo Gui Wan strips out the draining herbs and enriches yin, You Gui Wan starts from the same foundation of prepared rehmannia, yam, cornelian cherry, goji and dodder, and then adds cinnamon bark, prepared aconite, eucommia and angelica. The interesting part is the shape of the idea rather than the list of herbs: a large quantity of yin-enriching material is built in alongside a small quantity of hot, acrid ones. Zhang Jiebin's dictum - seek yang within yin, or the source runs dry - is the theory, and the composition is that theory written out.
The safety discussion has to be led by one herb. Prepared aconite carries aconitine-type alkaloids, which hold voltage-gated sodium channels open; poisoning runs from tingling and numbness through ventricular arrhythmia to asystole. In a decoction, prolonged boiling hydrolyses the diester alkaloids into far less toxic monoester and lipo-alkaloids, and that step is the single most important control in traditional practice. A honey pill is swallowed, not boiled. The hydrolysis step is therefore absent, and the safety of the product depends entirely on how well the root was processed before it ever went into the pill, and on how much of it is present - a figure this entry deliberately does not give. That is the honest reason to look for a named, regulated manufacturer and to avoid unlabelled products.
Cinnamon bark is the second caution, because cassia cinnamon contains coumarin, a compound with documented hepatotoxicity at sustained intake and an additive effect with anticoagulants. Cinnamon bark (rou gui) and cinnamon twig (gui zhi) come from the same tree but are not the same material. Angelica root and goji berry both have case reports of interaction with warfarin. Deer antler glue raises the same wildlife-control and vegetarian issues noted under Zuo Gui Wan. Prepared aconite, cinnamon and angelica are all traditionally avoided in pregnancy, and this formula is not used in acute illness or where clear heat signs are present.
What the formula addresses must also be read forward into the present. Chilliness, cold pain in the lower back, reduced sexual function, frequent night urination, oedema and early-morning diarrhoea are the classical picture, and they are also produced by hypothyroidism, anaemia, depression, low testosterone, diabetes, chronic kidney disease, heart failure and obstructive sleep apnoea, and by medicines - beta blockers, SSRIs, opioids and glucocorticoids among them. Erectile dysfunction in particular is now recognised as an early marker of endothelial dysfunction and cardiovascular risk rather than a local problem. Night urination deserves the same treatment: diabetes, prostatic enlargement, heart failure, sleep apnoea and diabetes insipidus are all on the list. The gate of life is a concept in this tradition, not a structure that can be imaged.
右归丸是这一对的另一半，出自同一部明代著作《景岳全书》。左归丸去泻药而纯补其阴；右归丸则在熟地、山药、山茱萸、枸杞、菟丝这个共同底盘上，加入肉桂、制附子、杜仲、当归。真正有意思的是配伍的思想而非药味清单：大量滋阴填精之品与少量辛热之品同炉。张介宾那句「善补阳者必于阴中求阳」是理论，这个配伍就是把理论写了一遍。
安全性必须从一个药味讲起。制附子含乌头碱类双酯型生物碱，它使电压门控钠通道持续开放；中毒过程从口舌肢体麻木，走到室性心律失常，再走到心脏停搏。汤剂里最重要的控制环节是久煎 —— 双酯型生物碱水解为毒性远低的单酯型与脂型生物碱。而蜜丸是吞服的，不经煎煮，这个水解环节因此缺失，成品安全完全落在「附子入丸之前炮制得如何」以及「方中投了多少」之上；后者本条目不列。这正是应当认准有名称可查、受监管的厂牌，并回避无标签产品的诚实理由。
第二处注意是肉桂。桂皮含香豆素，长期摄入的肝毒性有文献记载，与抗凝药合用有叠加效应。肉桂（树皮）与桂枝（嫩枝）同出一树而非同一物。当归与枸杞都各有与华法林相互作用的病例报告。鹿角胶涉及与左归丸条目相同的野生动物监管与素食问题。附子、肉桂、当归在孕期都属禁忌或慎用之列，外感、急性病与有明显热象者不用此方。
它所对的证也必须往今天推一遍。畏寒、腰膝冷痛、性功能减退、夜尿频多、水肿、五更泻是古典画面，而同样的表现由甲状腺功能减退、贫血、抑郁、低睾酮、糖尿病、慢性肾病、心力衰竭、睡眠呼吸暂停引起，也可由药物引起 —— β 受体阻滞剂、SSRI 类抗抑郁药、阿片类与糖皮质激素都在其中。勃起功能障碍尤其应当重新认识：它今天被视为血管内皮功能与心血管风险的早期标志，而不是一个局部问题。夜尿多同样需要走一遍清单：糖尿病、前列腺增生、心衰、睡眠呼吸暂停与尿崩症都在列。命门是这套传统里的一个概念，不是可以在影像上看到的结构。