Source 出处 · Jingui Yaolüe · Doses are not given here: they are set by a licensed practitioner for the individual.
Safety. What this formula is recorded for is 皮水 — skin water — and the line that records it is short: oedema of the four limbs, water in the skin, and 四肢聂聂动, a faint shivering or twitching movement in the limbs.
The word 水 in this chapter is translated as oedema, and oedema is one of the few complaints that can be measured directly today. What gets separated out first is not which classical category it belongs to but which mechanism is behind it, because the list is short and the tests are ordinary: bilateral pitting oedema points towards heart failure, kidney disease with loss of albumin, liver disease, low albumin from any cause, or a medicine — calcium channel blockers, non-steroidal anti-inflammatory drugs, some corticosteroids and some medicines for diabetes all appear on that list; oedema in one leg points towards deep vein thrombosis, or lymphatic or venous disease; oedema that does not pit points towards lymphatic obstruction or the myxoedema of an underactive thyroid; oedema worst around the eyes in the morning points towards the kidney.
The second clause, 四肢聂聂动, is the one more often passed over. A chapter about swelling records a movement in the limbs, and a reader today hears tremor or fasciculation. It is worth saying where that combination points without turning it into a diagnosis: fluid overload and muscle twitching appear together in the electrolyte disturbances — low potassium, low calcium, low magnesium — that follow from diuretic treatment and from impaired kidney function. A person who is oedematous is often a person who is being given a diuretic. Serum electrolytes and kidney function are checked, not assumed.
The materials carry a record that must be repeated every time 防己 appears, because the name covers more than one plant. 广防己, Aristolochia fangchi, was the material in the Belgian weight-loss clinic episode of the early 1990s, where it caused a distinctive rapidly progressive kidney fibrosis and a high rate of urothelial cancer in the same patients. Aristolochic acid is classed as a human carcinogen, and continued progression of the kidney injury after exposure has stopped is documented. The current Chinese Pharmacopoeia admits 粉防己, Stephania tetrandra, as the material for this name. This is not botanical pedantry: the name on the label is not by itself a guarantee of which plant is in the packet, and the consequence is permanent.
黄芪 is Astragalus root, a legume. 桂枝 is the young twig of Cinnamomum cassia; it contains cinnamaldehyde and coumarin. 茯苓 is the sclerotium of a fungus — it is not 土茯苓, which is an entirely different plant, and the two names are regularly confused. 甘草 is licorice root, and the glycyrrhizin in it can produce a state resembling excess mineralocorticoid: salt and water retention, potassium loss and raised blood pressure, described at ordinary amounts taken over weeks, and more serious in someone already taking a diuretic or digoxin.
Pregnancy is an absolute exclusion for this formula. Chinese-language clinical literature reports observations of formulas of this class in oedema, mostly small in scale and methodologically limited. This library records that such studies exist; it does not record that benefit has been established, and this entry is not a way of managing an episode of oedema.
本方所记的是**皮水** —— 皮肤里的水。条文很短：四肢肿，水气在皮肤中，四肢聂聂动。
本篇的「水」今天译作水肿，而水肿是少数能直接量出来的主诉之一。今天先要分开的不是它属于哪个古典类别，而是它背后是哪一种机制 —— 这张表很短，检查也很普通：**双侧凹陷性**指向心力衰竭、丢失白蛋白的肾病、肝病、各种原因的低白蛋白，以及药物（钙通道阻滞剂、非甾体抗炎药、部分糖皮质激素与部分降糖药都在这张表上）；**单侧**指向深静脉血栓、淋巴或静脉疾病；**按下去不凹陷**指向淋巴阻塞或甲状腺功能减退的黏液性水肿；**晨起眼睑面部最重**指向肾脏。
第二句「四肢聂聂动」是最容易被跳过去的。一篇讲肿的章节记下肢体里的一种动，今天的读者会听成震颤或肌束抽动。这里说清楚它把人指向哪里，而不把它变成一个诊断：**液体负荷与肌肉抽动同时出现在电解质紊乱里 —— 低钾、低钙、低镁 —— 而这些正是使用利尿剂与肾功能受损之后会发生的事**。一个水肿的人常常正在被给利尿剂；血电解质与肾功能是拿来查的，不是拿来假定的。
药味里有一条每次遇到防己都必须复述的记载：**这个名称下不止一种植物**。广防己（Aristolochia fangchi）就是 1990 年代初比利时减肥诊所事件的那一味：它引起一种特征性的快速进展性肾间质纤维化，并在同一批患者中出现很高比例的尿路上皮癌；马兜铃酸被列为人类致癌物，而且**停止接触之后肾损害仍继续进展**这一点有文献记载。现行《中国药典》以防己之名只收粉防己（Stephania tetrandra）。这里不是植物学上的咬文嚼字：**标签上的名字本身不能保证袋子里是哪一株**，而后果是不可逆的。
黄芪是豆科黄芪属的根。桂枝是肉桂（Cinnamomum cassia）的嫩枝，含桂皮醛与香豆素。茯苓是真菌的菌核，**不是土茯苓** —— 后者是完全不同的植物，两个名字经常被混。甘草是甘草的根，其中的甘草酸可引起**假性醛固酮增多症**：钠水潴留、失钾、血压升高，在「普通量连服数周」的情形下也有报告，对已经在用利尿剂或强心苷的人只会更重要而不是更次要。
**孕期是本方的绝对排除项。** 中文临床文献有本方一类方剂用于水肿的观察报告，多为小规模、方法学有限。本库记「有这类研究」，不记「疗效已被确立」；本条目也不构成对一次水肿发作的处置。