李氏云∶痈疽已安之后，或未安之际，口舌燥黄如鸡内金者，乃肾水枯竭，心火上炎，
此症最恶。古人云，玉华池竭七朝亡。若误投以丹药，祸在反掌，急用加减八味丸，桑枝煎五味
子汤，以滋补之。
愚按∶前症若不慎房事，亏损真阴，而虚火上炎，亦多患此。若发热作渴，或口舌生
疮，或小便频数，或茎中作痛，亦宜用前药（详见附录用药关键）。
桑枝方 大治口渴。取嫩桑枝细切一升炒，以水三升煎一升，日服五七剂，更多尤妙。
抱朴子云∶疗风痹干燥，臂痛香港脚，四肢拘挛，上气眩晕。久服补肺消食，利小便，轻身聪
明，令人光泽，其功不能尽述。
愚按∶桑枝补血气，生津液，轻身明目，补肺肾之良剂也。
五味子汤 治肾水枯涸，口燥舌干。
五味子（一两） 黄 （炒三两） 人参（二两） 麦门冬（一两） 粉草（炙五钱）
上每服五钱，水煎，日夜服五七剂。
愚按∶前药乃六一散、生脉散之复方，滋化源之良剂，若肾水既涸，虚火上炎，而口燥
作渴者，须佐以加减八味丸（详见附录用药关键）。
李氏曰∶一发背之热，未有不自肾虚而得之者，必须五更服加减八味丸。
愚按∶前论诚为启发后人，垂惠永久。盖发背脑疽，皆由肾经湿热，虚火上炎，中传恶
症；若非加减八味丸滋肾水以制心火，补中益气以生化源，欲望其生，难矣。启玄子云∶大
寒而甚，热之不热，是无火也，当助其心。大热而甚，寒之不寒，是无水也，当益其肾。夫
寒之不寒，责其无水，热之不热，责其无火；热之不久，责心之虚，寒之不久，责水之少。
窃谓无火者，当用八味丸以益其心；无水者，当用六味丸以滋其肾（治验见前四十二论）。
Li stated: After the carbuncle and ulcer (Yong Ju) has stabilized, or while it is still unstable, if the mouth and tongue are dry and yellow like chicken gizzard lining, this indicates exhaustion of Kidney Water and flaming up of Heart Fire. This condition is most malignant. The ancients said, "When the Jade Flower Pool (referring to oral fluids) dries up, death occurs in seven days." If mistakenly administered with elixirs (Dan Yao), disaster will strike in an instant. One must urgently use Modified Ba Wei Wan (Eight-Ingredient Pill with Rehmannia) and a decoction of Mulberry Twig and Schisandra Berry to nourish and tonify.
My commentary: Regarding the aforementioned symptoms, if one fails to exercise caution regarding sexual activity, depleting True Yin, and causing Deficient Fire to flare upward, this condition is also frequently observed. If accompanied by fever and thirst, sores on the mouth and tongue, frequent urination, or pain in the urethra, the aforementioned medicines should also be used (see Appendix for Key Principles of Medication).
Mulberry Twig Formula: Greatly treats thirst. Take fresh tender Mulberry Twig, finely cut one sheng, stir-fry it, add three sheng of water, and decoct until one sheng remains. Take five to seven doses daily; taking more is even better.
Baopuzi stated: It treats wind-bi dryness, arm pain, beriberi, limb spasms, rebellious Qi, and vertigo. Long-term consumption tonifies the Lung, aids digestion, promotes urination, lightens the body, sharpens hearing and vision, gives luster to the skin, and its merits cannot be fully described.
My commentary: Mulberry Twig nourishes Blood and Qi, generates body fluids, lightens the body, improves vision, and is an excellent agent for tonifying the Lung and Kidney.
Schisandra Berry Decoction: Treats exhaustion of Kidney Water, dry mouth, and parched tongue.
Schisandra Berry (Wuweizi) (1 liang)
Astragalus Root (Huangqi) (stir-fried, 3 liang)
Ginseng Root (Renshen) (2 liang)
Ophiopogon Tuber (Maimendong) (1 liang)
Licorice Root (Fencao) (roasted, 5 qian)
Take 5 qian of the above herbs per dose, decoct in water, and take five to seven doses day and night.
My commentary: The aforementioned medicine is a compound formula of Liu Yi San (Six-to-One Powder) and Sheng Mai San (Generate the Pulse Powder), which is an excellent agent for nourishing the source of transformation and generation (Spleen/Stomach). If Kidney Water is exhausted and Deficient Fire flares upward, causing dry mouth and thirst, it is necessary to assist with Modified Ba Wei Wan (see Appendix for Key Principles of Medication).
Li stated: The heat associated with Back Carbuncle (Fa Bei) invariably originates from Kidney Deficiency; therefore, Modified Ba Wei Wan must be taken at wu geng (between 3 am and 5 am).
My commentary: The preceding discussion indeed enlightens future generations and benefits them permanently. Generally, Back Carbuncle and Brain Ulcer (Nao Ju) arise from Damp-Heat in the Kidney Meridian and Deficient Fire flaming upward, transmitting inward to become malignant syndromes. Unless one uses Modified Ba Wei Wan to nourish Kidney Water to control Heart Fire, and tonifies Middle Qi to generate the source of transformation, hoping for survival would be difficult. Qixuanzi stated: "Extreme cold that does not warm up despite heat therapy indicates absence of Fire (Mingmen Fire Decline); one should assist Heart Yang. Extreme heat that does not cool down despite cold therapy indicates absence of Water (Kidney Yin Deficiency); one should benefit Kidney Yin." Failure to resolve cold is attributed to lack of Water; failure to resolve heat is attributed to lack of Fire. If heat resolves only briefly, the fault lies in Heart Deficiency; if cold resolves only briefly, the fault lies in insufficient Water.
I propose: For those with "absence of Fire," one should use Ba Wei Wan to benefit Heart and Kidney Fire; for those with "absence of Water," one should use Liu Wei Wan (Six-Ingredient Pill with Rehmannia) to nourish Kidney Yin (clinical cases seen in Discussion 42).