老人夜间睡眠时感到口干并伴有滑泄（大便失禁或遗精），可以取自己的尿液，不时饮用一杯，能够延长寿命。这是利用人体自身的“坎”（肾水/阴）与“离”（心火/阳）相交的原理。
硫黄（经过炮制，一斤） 青黛（飞研过，一两六钱）
将硫黄制成丸药，用青黛作为包衣。
对于体内寒痰旺盛的老人，服用此方可以祛除疾病、延年益寿。
硫黄是火的精华，人没有这团阳气就不能生存，所以用它来补益命门之火。用青黛做外衣，是为了制约硫黄的燥热之性，防止其灼伤咽喉。
年老体弱的人，依靠草木金石类药物难以滋养气血，所以使用上述血液和精气类的物质入药进行调和，以配合服用和食疗。取其同类相从的道理，滋养起来就容易多了。七十岁以后不吃肉就不能饱腹，也是这个意思。
In the elderly, who experience dry mouth and seminal emission or diarrhea during night sleep, one may collect their own urine and drink a cup occasionally to prolong life. This utilizes the interaction between the Kan (Kidney Water/Yin) and Li (Heart Fire/Yang) within one's own body.
Shihuang (Sulfur, processed, 1 jin) Qingdai (Realgar Blue/Fly-dust, 1 liang 6 qian)
Make pills with Shihuang (Sulfur), and coat them with Qingdai (Realgar Blue).
For the elderly suffering from abundant internal cold-phlegm, taking this formula can eliminate disease and extend longevity.
Shihuang (Sulfur) is the essence of fire; humans cannot survive without this fire, hence it is used to benefit the Fire (Mingmen Fire). Using Qingdai (Realgar Blue) as a coating serves to restrain its drying and irritating nature.
For those of old age and weak constitution, wood, stone, and mineral drugs cannot adequately nourish Qi and Blood. Therefore, substances derived from blood and Qi are used in medicine for harmonization, to be taken alongside diet. The principle is that similar things attract each other, making nourishment easier. Even the saying that those over seventy must eat meat to feel full reflects this same idea.