味辛、甘，性冷，无毒。治心热烦躁，并五脏宿滞、症结。明目，退膈上虚热，消
肿毒。此即朴硝炼成者。（新补见《药性论》并日华子。）
仙经∶以朴硝制伏为玄明粉。朴硝是太阴之精华，水之子也。阴中有阳之药。太阴号曰
玄
，内搜众疾，功莫大焉。治一切热毒风，搜冷， 癖气胀满，五劳七伤，骨蒸传尸，头痛烦
热，搜除恶疾，五脏秘涩，大小肠不通，三焦热淋，疰忤疾，咳嗽呕逆，口苦干涩，咽喉闭
塞，心、肝、脾、肺脏胃积热，惊悸，健忘，荣卫不调，中酒中脍，饮食过度，腰膝冷痛，
手脚酸，久冷久热，四肢壅塞，背膊拘急，眼昏目眩，久视无力，肠风痔病，血癖不调。妇
人产后，小儿疳气，阴毒伤寒，表里疫疠等疾，并悉治之。此药久服令人身轻耳明，驻颜延
寿。急解毒药，补益，妙。唐明皇帝闻说终南山有道士刘玄真，服食此药，遂诏而问曰∶朕
闻卿寿约三百岁，服食何药，得住世间，充悦如此。玄真答曰∶臣按《仙经》修炼朴硝，号
玄明粉，只服此药，遂无病长生。其药无滓，性温，能除众疾。生饵尚能救急难性命，何况
修炼长服。益精壮气，助阳证阴。不拘丈夫妇人，幼稚襁褓，不问四时冷热，即食后冷热俱
治。一两分为十二服，但临时酌量加减。似觉壅热，伤寒，头痛鼻塞，四肢不举，饮食不下
，烦闷气胀，不论昼夜急疾，要宣泻求安，即看年纪高下，用药一分或至半两，酌量加减，
用桃花汤下为使，最上；次用葱汤下；如未通宣，更以汤一碗或两碗，投之即验。自然调补
如常
。要微畅不秘涩，但长服之，稍稍得力，朝服暮服，应不搜刮人五脏，怡怡自泰。其药初服
之时，每日空腹，酒饮茶汤任下三钱匕，食后良久更下三钱匕。七日内常微泻利黄黑水涎沫
等，此是搜淘诸疾根本出去，勿用畏之。七日后渐觉腹脏暖，消食下气，唯忌食苦参或食诸
鱼、藕菜。饮食诸毒药解法，用葱白煎汤一茶碗，调玄明粉两钱顿服之，其诸毒药立泻下。
若女人身怀六甲，长服安胎，诞孩子生日，无疮肿疾病。长服除故养新，气血日安。如有偶
中毒物，取地胆一分，荠 、犀角各半两，服之立解。如长服，用大麻汤下为使。此药偏暖
水脏，女人服，补血脉，及治骨蒸五劳，惊悸健忘，热毒风等，服之立愈。令人悦泽，开关
健脾，轻身延寿，驻精神，明目。诸余功效不可具载，有传在太阴经中。朴硝二斤，须是白
净者，以瓷炉一个叠实，却以瓦一片盖炉，用十斤炭火一 ，炉口不盖，着炭一条，候沸定
了，方盖之，复以十五斤炭 之。放冷一伏时，提炉出药，以纸摊在地上，盆盖之一伏时，
日晒取干。入甘草二两，生熟用，细捣罗为末。
味辛、甘，性冷，无毒。治疗心热烦躁，以及五脏积滞、症结。明目，消除膈上虚热，消肿毒。这就是由朴硝炼制而成的。（新增内容见于《药性论》及日华子著作。）
仙经记载：用朴硝加工制成玄明粉。朴硝是太阴（脾/肺经气机）的精华，属水之子。这是一种阴中寓阳的药物。太阴被称为“玄”，内能搜剔各种疾病，功效没有比它更大的了。治疗一切热毒风邪，搜剔冷积，癖气胀满，五劳七伤，骨蒸传尸（结核病等慢性消耗性疾病），头痛烦热，搜除恶疾，五脏秘涩，大小肠不通，三焦热淋，疰忤疾（注病、客忤），咳嗽呕逆，口苦干涩，咽喉闭塞，心、肝、脾、肺、胃脏腑积热，惊悸，健忘，营卫不调，醉酒或过食肉类，饮食过度，腰膝冷痛，手脚酸痛，久冷久热，四肢壅塞，背膊拘急，眼昏目眩，久视无力，肠风痔病，血癖不调。妇人产后，小儿疳气，阴毒伤寒，表里疫疠等各种疾病，都能治疗。此药长期服用使人身体轻盈、耳聪目明，驻颜延寿。紧急解毒，补益作用，非常奇妙。唐明皇听说终南山有道士刘玄真服食此药，于是下诏询问说：“我听说你寿命约三百岁，服食什么药物，能在世间长寿，如此充盈喜悦？”玄真回答说：“臣按照《仙经》修炼朴硝，称为玄明粉，只服食此药，便无病长生。此药无渣滓，性温，能除众疾。生吃尚能救急难性命，何况经过修炼长期服用。益精壮气，助阳证阴。不拘男女老少，不问四季冷热，饭后冷热皆治。一两分为十二次服用，根据当时情况酌情加减。如果感觉壅热，伤寒，头痛鼻塞，四肢不能举动，饮食不下，烦闷气胀，不论昼夜急疾，需要宣泻以求安宁，就根据年龄高低，用药一分至半两，酌情加减，用桃花汤送服为最佳；其次用葱汤送服；如未通宣，再灌一碗或两碗汤剂，立即见效。自然调补如常。要使大便微畅而不秘涩，只要长期服用，逐渐得力，早晚服用，不会搜刮人体五脏，心情愉悦安泰。此药初服时，每日空腹，用酒、饮、茶汤任选送服三钱匕，食后很久再服三钱匕。七日内常有轻微腹泻，排出黄黑水涎沫等，这是搜淘清除各种疾病的根本，不要害怕。七日后渐渐觉得腹脏温暖，消食下气，唯独忌食苦参或各种鱼、藕菜。饮食各种毒药的解法，用葱白煎汤一茶碗，调玄明粉两钱顿服，各种毒药立即泻下。若女人身怀六甲，长期服用可安胎，分娩生子时，无疮肿疾病。长期服用除旧养新，气血日渐平安。如有偶然中毒物，取地胆一分，荠苨、犀角各半两，服之立即解救。如长期服用，用大麻汤送服为使药。此药偏暖水脏，女人服用，补血脉，及治疗骨蒸五劳，惊悸健忘，热毒风等，服之立即痊愈。令人容颜光泽，开关健脾，轻身延寿，驻精神，明目。其他功效不可尽载，有流传在太阴经中。朴硝二斤，必须是白净的，用一个瓷炉叠实，再用一片瓦盖住炉口，用十斤炭火煅烧，炉口不盖，放一条炭，等沸腾稳定后，才盖上，再用十五斤炭覆盖。冷却一个时辰，取出炉中药，铺纸在地上，用盆盖住一个时辰，日晒取干。加入甘草二两，生用或熟用，细捣罗为末。”
Pungent and sweet in flavor, cold in nature, non-toxic. Treats heart-heat with irritability, as well as stagnation in the five zang organs and mass formations (zheng jie). Brightens the eyes, clears deficiency-heat above the diaphragm, and reduces swelling and toxicity. This is refined from Puxiao (Mirabilite). (Newly added content appears in *Yaoxing Lun* and the works of Ri Huazi.)
The Immortal Canon states: Xuanmingfen is prepared by processing Puxiao. Puxiao is the essence of Taiyin (the spleen/lung qi mechanism), the son of water. It is a medicine that contains yang within yin. Taiyin is called "Xuan" (Mysterious), which internally searches out various diseases; its efficacy is unparalleled. It treats all kinds of wind-heat-toxins, searches out cold accumulations, pi-mass (fixed masses) with distension and fullness, wulao qishang (five exhaustions and seven injuries), bone-steaming tuberculosis (chuan shi), headache with fever, searches out evil diseases, constipation of the five zang organs, obstruction of the large and small intestines, heat-strangury of the sanjiao, zhu-wu disease (infectious or miasmic diseases), cough with vomiting and reflux, dry mouth and throat, throat obstruction, accumulation of heat in the heart, liver, spleen, lungs, and stomach, palpitations, forgetfulness, disharmony of ying and wei, alcohol intoxication or overconsumption of meat, dietary excess, cold pain in the lower back and knees, soreness and weakness of hands and feet, chronic cold or heat, obstruction of the four limbs, stiffness of the back and shoulders, blurred vision and dizziness, weakness after prolonged eye use, intestinal wind with hemorrhoids, blood stasis with irregular menstruation. For postpartum women, children with gan-qi (malnutrition syndrome), yin-poison shaoyin disease, epidemic diseases affecting both interior and exterior, it treats all these conditions. Long-term use of this medicine makes the body light and the ears clear, preserves youth, and prolongs life. In emergencies to detoxify and for tonification, it is miraculous. Emperor Ming of Tang heard that Daoist Liu Xuenzhen in Zhongnan Mountain consumed this medicine, so he issued an edict to ask: "I hear you live to about three hundred years old. What medicine do you consume to remain in the world so vigorous and joyful?" Xuenzhen replied: "According to the Immortal Canon, I refine Puxiao into Xuanmingfen. By consuming only this medicine, I have no illness and achieve longevity. This medicine has no dregs, is warm in nature, and eliminates various diseases. Even raw consumption can save lives in emergencies, let alone refined long-term use. It benefits essence and strengthens qi, assists yang and verifies yin. It applies to men and women, young and old, regardless of seasonal cold or heat, treating conditions after meals whether cold or hot. Divide one liang into twelve doses, adjusting according to circumstances. If one feels obstructed heat, shaoyin disease, headache with nasal congestion, inability to move limbs, difficulty eating, restlessness and abdominal distension, regardless of day or night urgency, requiring purgation for relief, adjust the dose based on age from one fen to half a liang. Administer with Taohua Tang (Peach Blossom Decoction) as the best vehicle; secondly with Congtang (Scallion Decoction); if not yet unobstructed, administer another bowl or two of decoction immediately for effect. Natural regulation and tonification resume as usual. To ensure slight bowel movement without constipation, long-term use gradually takes effect. Morning and evening administration will not deplete the five zang organs, leaving one peaceful and content. When first taking this medicine, take three qianbi on an empty stomach daily with wine, drink, or tea, and another three qianbi long after meals. Within seven days, mild diarrhea with yellow-black watery saliva may occur; this is the expulsion of the root causes of various diseases, do not fear it. After seven days, the abdomen and viscera gradually feel warm, digestion improves, and qi descends. Avoid bitter sophora root (Kushen) or any fish, lotus root, and vegetables. The antidote for dietary poisons is to decoct scallion whites in one teacup of water, mix with two qian of Xuanmingfen, and take at once; various poisons are immediately purged. For pregnant women, long-term use calms the fetus; upon delivery, there are no sores or diseases. Long-term use removes the old and nourishes the new, stabilizing qi and blood daily. In case of accidental poisoning, take one fen of Dichan (Euphorbia kansui), half a liang of Qini (Nephrolepis rhizome) and Xijiao (Rhinoceros Horn), and the poison is instantly resolved. For long-term maintenance, administer with Damatang (Hemp Seed Decoction) as the vehicle. This medicine specifically warms the water organ; for women, it nourishes blood vessels and treats bone-steaming wulao, palpitations, forgetfulness, and wind-heat-toxin, with immediate recovery. It enhances complexion, opens orifices, strengthens the spleen, lightens the body, prolongs life, conserves spirit, and brightens the eyes. Other effects cannot be fully listed; some are recorded in the Taiyin Jing. Take two jin of Puxiao, ensuring it is white and clean. Place it in a solidly stacked porcelain furnace, cover the furnace mouth with a tile, and burn with ten jin of charcoal. Do not cover the furnace mouth initially; place one piece of charcoal inside. Wait until boiling stabilizes, then cover it, and add fifteen jin of charcoal to cover completely. Allow to cool for one fu period (approx. 2 hours). Remove the medicine from the furnace, spread it on paper on the ground, cover with a basin for one fu period, and sun-dry to obtain dry powder. Add two liang of Gancao (Licorice Root), used raw or processed, finely pounded and sieved into powder."