小儿无补肾法，盖禀父精而生，此天一生水，化生之源，肾之根也。此根日赖脾胃乳食水谷长养，男
至十六而肾始充满；既满之后，婚媾妄用亏损，则可用药补之。若受胎之时，禀之不足，则无可补；禀之
原足，又何待于补耶？
愚按小儿行迟、齿迟、解颅、囟填、五软、鹤膝、肾疳、齿豁、睛白、多愁，凡此皆因禀受肾气不足，
当以六味地黄丸加鹿茸补之。若因精气未满，而御女以通，多致头目眩晕、作渴、吐痰，或发热足热、腰
腿酸软，或自汗盗汗、二便涩痛，变生诸疾，难以名状。余常用六味、八味二丸及补中益气之剂加减用
之、无不奏效。
一小儿，九岁，解颅，足软，两膝渐大，不能行履，属肾禀不足。用六味丸加鹿茸，三月而能步履。
一小儿，十四岁，肢体倦怠，发热，晡热，口干作渴，吐痰如涌，小便淋沥，或面目赤色，身不欲衣，
此亦禀赋不足也。用补中益气汤及前丸而愈。
一小儿，十五岁而御女，大小便道牵痛，服五苓散之类，虚症蜂起，与死为邻。余用补中益气汤、加
减八味丸而愈。
一小儿，十三岁，内热，晡热，形体倦怠，食少，作渴，或用清热等药治之，虚症悉具。余以为所禀怯
弱，用六味丸加鹿茸补之，不越月而痊。盖古今元气虚实不同故也。
There is no specific method for tonifying the Kidney in children, because they are conceived by inheriting the father's essence. This corresponds to the principle of "Heaven generates One and Water," which is the source of transformation and generation, and the root of the Kidney. This root relies daily on the nourishment from milk, food, and water and grain processed by the Spleen and Stomach to grow. A boy's Kidney Qi begins to become full only at the age of sixteen; after it is full, if deficiency occurs due to excessive sexual activity following marriage, then medicinal tonification can be used. If the congenital endowment was insufficient at the time of conception, there is nothing that can be supplemented; if the original endowment was sufficient, why would supplementation be necessary?
My commentary: Conditions such as delayed walking, delayed tooth eruption, Jie Lu (delayed closure of fontanelles), Xian Tian (bulging fontanelles), Wu Ruan (weakness of the head/neck, mouth, hands, feet, and muscles), He Xi Feng (crane-knee deformity), Shen Gan (Kidney rickets), loose teeth, excessive sclera visibility, and melancholy are all caused by insufficient congenital Kidney Qi. These should be treated with Liu Wei Di Huang Wan (Six-Ingredient Pill with Rehmannia) added with Lu Rong (Cervus Nippon Cornu). If sexual intercourse occurs prematurely before Essence and Qi are fully matured, it often leads to dizziness, thirst, expectoration, fever, heat in the feet, soreness and weakness of the waist and legs, spontaneous sweating, night sweats, or painful and difficult urination and defecation, giving rise to various diseases with complex symptoms difficult to describe. I commonly use modifications of Liu Wei Di Huang Wan (Six-Ingredient Pill with Rehmannia), Ba Wei Di Huang Wan (Eight-Ingredient Pill with Rehmannia), and Bu Zhong Yi Qi Tang (Tonify the Middle and Augment the Qi Decoction), achieving consistent efficacy.
A nine-year-old child presented with Jie Lu (delayed closure of fontanelles), weak legs, gradually enlarging knees, and inability to walk, attributable to insufficient congenital Kidney endowment. Treatment with Liu Wei Di Huang Wan (Six-Ingredient Pill with Rehmannia) added with Lu Rong (Cervus Nippon Cornu) allowed him to walk after three months.
A fourteen-year-old child presented with limb fatigue, fever, afternoon tidal fever, dry mouth and thirst, profuse expectoration, dribbling urine, sometimes red face and eyes, and aversion to clothing. This was also due to insufficient congenital endowment. Recovery was achieved using Bu Zhong Yi Qi Tang (Tonify the Middle and Augment the Qi Decoction) combined with the aforementioned pill.
A fifteen-year-old child engaged in sexual intercourse prematurely, resulting in pulling pain in the urinary and intestinal tracts. After taking formulas similar to Wu Ling San (Five-Ingredient Powder with Poria), deficiency symptoms arose rapidly, bringing him near death. I treated him with Bu Zhong Yi Qi Tang (Tonify the Middle and Augment the Qi Decoction) and modified Ba Wei Di Huang Wan (Eight-Ingredient Pill with Rehmannia), resulting in recovery.
A thirteen-year-old child presented with internal heat, afternoon tidal fever, physical fatigue, poor appetite, and thirst. When treated with heat-clearing medications, deficiency symptoms manifested completely. I attributed this to his weak congenital constitution and treated him with Liu Wei Di Huang Wan (Six-Ingredient Pill with Rehmannia) added with Lu Rong (Cervus Nippon Cornu). He recovered within a month. This is because the constitution of Yuan Qi (Original Qi) differs between ancient and modern times.