The 少阴 version of 真武汤
By Karina • Jun 26th, 2008 • Category: Cardiovascular, Kidney, shanghanlunThe situation:
“少阴病，二三日不已，至四五日，腹痛，小便不利，四肢沉重疼痛，自下利者，此为有水气。
其人或咳，或小便利，或下利，或呕者，真武汤主之。”
This guy has a shaoyin illness which does not resolve in 2-3 days. Until the 4th-5th day, his abdomen starts hurt, his urine doesn’t come out too smoothly and his four limbs feel heavy and aching all over. And he’s got diarrhea too. This is called 水气 aka water-qi.
If he’s coughing, or his urine’s flowing out smoothly, or he’s got diarrhea, or he’s vomiting, use 真武汤.
An analysis:
This is situation is rather different than the 太阳病 (Greater Yang Disease) version of 真武汤’s use.
That situation sounded slightly more acute, whereas here, we’re having what seems like some chronic illness. And in this sitｕation, the patient has 水气, which to me is edema. What kind of edema? Probably full-body, starting with the lower limbs, probably related to cardiovascular and renal debility. The patient probably already has Nephrotic Sundrome and CHF. The abdominal pain is probably an outlier here, either not directly related to the cause of edema or just a pain due to edema. Or it could be a digestive disorder related to the diarrhea?
Yes, the diarrhea is the one that’s difficult to resolve. Could be just an accompanying illness, or a constitutional weakness that the patient already has. In any case, his heart and kidneys aren’t good.
Using 真武汤 here:
It fits the bill pretty well, very similar to the other 少阴寒化证 prescriptions that are of the 姜附 variety (e.g. 四逆汤，附子汤). Something worth pondering is why 生姜 is used instead of 干姜.
Can we think of it as just another formula that rides of the success of 附子? In a way, yes. It is 附子 that is able to on one hand stave off the excess of hypovolemic shock - not enough fluids in the system. Then again, 附子 is also able to turn up water metabolism (by driving down M-receptor numbers and cGMP levels), hence placating an edema event.
On the other hand, 真武汤 is slightly more well-rounded than a decoction like 四逆汤. It has 茯苓, which while a diuretic, may also contribute to fluid generation. It has 生姜 and 白术 while are milder herbs good for the digestive system. And it also has 芍药. But no 甘草 (licorice)… Why?