一名青盐。补肾、泻血热。
甘咸而寒。入肝肾。助水脏。平血热。治目痛赤涩。（散肝经风热。）吐血溺血，齿舌出
血，
坚骨固齿。（擦牙良。）明目乌须。功同食盐而更胜之。出西羌。不假煎炼。方棱明莹色青者
良。（风眼烂弦、戎盐化水点之。）
泻热。
辛咸大寒。治时气热盛。口渴水肿。盐精渗入土中。年久结成。清莹有棱。入水即化。
亦名
寒水石。（古方所用寒水石、是凝水石、唐宋诸方用寒水石、即石膏。）
泻热救阴。
太阴之精。咸寒而降。治上盛下虚。救阴助阳。（同硫黄、硝石用。）有扶危拯逆之功。
（正
阳丹、用治伤寒壮热、来复丹、用治伏暑热泻。）出解池。通泰积盐处。咸卤所结。青白莹
彻。片皆六棱者良。（今世用者、多是绛石。）
即皮硝。大泻、润燥、软坚。
芒硝、辛能润燥。咸能软坚。苦能下泄。大寒能除热。朴硝、酷涩性急。芒硝、经炼稍
缓。
能荡涤三焦肠胃实热。推陈致新。（与大黄同、盖邪气不除、正气不能复也。）治阳强之病。
伤寒。（经曰∶人之伤于寒也、必病热、盖寒郁而为热也。）疫痢。积聚结癖。留血停痰。黄
疸淋闭。瘰 疮肿。目赤障翳。通经堕胎。（经疏云∶硝者消也、五金八石、皆能消之、况
脏腑之积聚乎、其直往无前之性、所谓无坚不破、无热不荡者也、病非邪实深固、闭结不通
、不可轻投、恐误伐下焦真阴故也、无己曰∶热淫于内、治以咸寒、气坚者以咸软之、热盛
者以寒消之、故仲景大陷胸汤、大承气汤、调胃承气汤、皆用芒硝以软坚去实热、结不至坚
者、不可用也、佐之以苦、故用大黄相须为使、按芒硝消散、破结软坚、大黄推荡、走而不
守、故二药相须、同为峻下之剂、好古曰∶本草言芒硝堕胎、然妊娠伤寒可下者、兼用大黄
以润燥、软坚、泻热、而母子相安、经曰∶有故无殒、亦无殒也、此之谓欤、谓药自病当之
、故胎无患也。）硝能柔五金。化七十二石为水。生于卤地。刮取煎炼。在底者为朴硝。在
上者为芒硝。有牙者为马牙硝。置风日中。消尽水气。轻白如粉为风化硝。大黄为使。（本
经别录、朴硝、硝石虽分二种、而气味主治略同、后人辨论纷然、究无定指、时珍曰∶朴硝
下降、属水性寒、硝石为造炮焰硝、上升、属火性温。）
【戎盐】
又名青盐。具有补肾、清除血热的功效。
味道甘咸，性质寒凉。归入肝经和肾经。能辅助肾脏（水脏），平息血热。治疗眼睛疼痛、红肿干涩。（可疏散肝经的风热。）治疗吐血、尿血，牙齿和舌头出血，坚固骨骼和牙齿。（用来擦牙效果很好。）明目，使头发变黑。功效与食盐相同但更为显著。产于西羌地区。不需要经过煎煮提炼。形状呈方棱状、透明晶莹且颜色发青的为佳品。（风眼烂弦症，可将戎盐溶于水后滴眼。）
【朴硝】
具有泻热功效。
味道辛咸，性质大寒。治疗时行气分热盛。治疗口渴、水肿。盐精渗入土壤中，经年累月凝结而成。质地清澈晶莹且有棱角，入水即化。也叫做寒水石。（古方中使用的寒水石，实际上是凝水石；唐宋时期各方剂中使用的寒水石，则是石膏。）
具有泻热救阴的功效。
是太阴之精。味道咸寒，性质沉降。治疗上实下虚证。挽救阴液，辅助阳气。（与硫黄、硝石配合使用。）有扶正救逆的功效。（正阳丹，用于治疗伤寒壮热；来复丹，用于治疗伏暑引起的热性腹泻。）产于解池，是通泰等地积盐之处。由咸卤凝结而成。颜色青白、通透晶莹，片状且具备六个棱角的为佳品。（当今世面使用的，大多是无定形的绛石。）
【芒硝】
就是皮硝。具有强力泻下、润燥、软坚的功效。
芒硝，辛味能润燥，咸味能软坚，苦味能泄下，大寒之性能除热。朴硝味道酷烈苦涩，药性急猛；芒硝经过炼制后，药性稍缓。能够荡涤三焦和肠胃的实热，推陈出新。（与大黄同用，因为邪气不除去，正气就无法恢复。）治疗阳强病。伤寒。（《内经》说：人受寒邪侵袭，必然发热，这是因为寒气郁结而化为热。）疫痢。积聚癖块。瘀血停痰。黄疸、淋证、小便闭塞。瘰疬、疮肿。眼睛红赤、障翳。通经堕胎。（《本草经疏》说：硝，意为消解，五金八石都能被它消解，何况脏腑的积聚呢？它具有直往无前的药性，所谓无坚不破，无热不荡。如果不是邪气深固、闭结不通的实证，不可轻易投用，恐怕会误伤下焦的真阴。无己说：热邪蕴结于内，用咸寒之法治疗，气机坚结的用咸味来软化它，热盛的用寒性来消除它。所以张仲景的大陷胸汤、大承气汤、调胃承气汤，都使用芒硝来软坚去除实热，如果结聚不到坚硬程度，是不可用的。佐以苦味，所以用大黄作为辅助。按：芒硝消散破结、软坚，大黄推荡下行、走而不守，所以这两味药相互协同，同为峻下的方剂。好古说：本草记载芒硝能堕胎，然而妊娠期间患伤寒需要攻下的，兼用大黄来润燥、软坚、泻热，母子就能平安。《内经》说：有病则病受之，不会伤害胎儿，也不会伤害母体，说的就是这个道理。意思是药物作用于病灶，所以胎儿没有危险。）硝能柔化五金，将七十二种石头化为水。生于盐碱之地。刮取后煎煮提炼。沉淀在底部的称为朴硝。浮在上层的称为芒硝。有结晶牙齿状的称为马牙硝。放置在风吹日晒处，蒸发尽水分，变得轻白如粉的称为风化硝。以大黄为使药。（《本经别录》指出，朴硝和硝石虽然分为两种，但气味主治大致相同，后人争论纷纷，最终没有定论。李时珍说：朴硝性质下降，属水性寒；硝石用于制造炮焰硝，性质上升，属火性温。）
[Rongyan (Roc Salt)]
Also known as Qingyan (Green Salt). It tonifies the Kidney and clears Blood-heat.
It is sweet, salty, and cold in nature. It enters the Liver and Kidney meridians. It assists the Water Organ (Kidney), calms Blood-heat, and treats eye pain with redness and dryness. (It disperses Wind-heat from the Liver meridian.) It treats hematemesis (vomiting blood), hematuria (blood in urine), bleeding from teeth and tongue, strengthens bones and teeth (effective for brushing teeth), brightens the eyes, and darkens hair. Its efficacy is similar to common salt but superior. It originates from the Western Qiang region. It does not require boiling or refining. Those that are square-edged, transparent, crystal-clear, and greenish in color are of good quality. (For wind-eye with ulcerated eyelid margins, dissolve Rongyan in water and apply as drops.)
[Puxiao (Crude Saltpeter)]
It purges heat.
It is acrid, salty, and extremely cold in nature. It treats epidemic Qi with excessive heat. It treats thirst and edema. Salt essence seeps into the soil and crystallizes over years. It is clear, pure, and edged; it dissolves immediately upon contact with water. It is also called Hanshuishi (Cold Water Stone). (The Hanshuishi used in ancient prescriptions refers to Ningshuishi (Condensing Water Stone); the Hanshuishi used in Song and Tang dynasty prescriptions is actually Shigao (Gypsum Fibrosum).)
It purges heat and saves Yin.
It is the essence of Taiyin. It is salty and cold, with a descending nature. It treats excess above and deficiency below. It rescues Yin and assists Yang. (Used together with Liuhuang (Sulfur) and Xiaoshi (Niter).) It has the merit of supporting critical conditions and reversing adverse situations. (Zhengyang Dan is used to treat severe fever in Shanghan [Cold Damage]; Laifu Dan is used to treat summer-heat retention with diarrhea.) It originates from Jiechi, an area where salt accumulates in Tongtai. It forms from saline brine. Those that are greenish-white, transparent, and crystalline, with six-edged flakes, are of good quality. (What is commonly used today is mostly Jiangshi [Red Stone].)
[Mangxiao (Refined Saltpeter)]
It is the same as Pixiao (Skin Saltpeter). It strongly purges, moistens dryness, and softens hardness.
Mangxiao: Acridity moistens dryness; saltiness softens hardness; bitterness drains downward; extreme cold eliminates heat. Puxiao is harsh, astringent, and acts swiftly; Mangxiao, after refining, acts more mildly. It can cleanse the Sanjiao (Triple Burner) and intestines/stomach of excess heat, pushing out the old to bring forth the new. (When used with Dahuang [Rhubarb], because if pathogenic factors are not eliminated, healthy Qi cannot recover.) It treats Yang-excess conditions. Shanghan [Cold Damage]. (The Classic states: When humans are injured by Cold, they inevitably develop heat, because Cold stagnates and transforms into heat.) Yi li (Epidemic dysentery). Accumulations and masses. Retained Blood and stagnant Phlegm. Jaundice, Lin syndrome (dysuria), and urinary obstruction. Luoli (scrofula) and sores/swellings. Red eyes and cataracts. Unblocks menstruation and induces abortion. (Bencao Jing Shu states: Xiao means to eliminate. It can eliminate the five metals and eight stones, let alone accumulations in the Zang-Fu organs. Its nature charges forward unimpeded, described as "nothing is too hard to break, no heat is too great to purge." If the disease is not characterized by deep-seated pathogenic excess and blockage, it should not be lightly administered, lest it damage the True Yin of the Lower Jiao. Wuji stated: When Heat dominates internally, treat with salty-cold methods; use saltiness to soften firmness; use cold to eliminate excess heat. Therefore, Zhang Zhongjing's Da Xianxiong Tang, Da Chengqi Tang, and Tiaowei Chengqi Tang all use Mangxiao to soften hardness and remove excess heat. If the accumulation is not hard, it should not be used. Assisted by bitter herbs, hence Dahuang is used as an assistant. Analysis: Mangxiao dissipates, breaks knots, and softens hardness; Dahuang pushes down, moves without staying put. Thus, these two drugs synergize as potent purgatives. Haoguo stated: Materia Medica records that Mangxiao causes abortion. However, in pregnancy complicated by Shanghan requiring purgation, using Dahuang concurrently to moisten dryness, soften hardness, and purge heat ensures safety for both mother and fetus. The Classic states: "If there is a cause [pathology], there will be no injury," meaning the drug targets the pathology, thus sparing the fetus.) Xiao can soften the five metals and dissolve seventy-two types of stones into water. It grows in saline lands. It is scraped and refined. The substance settling at the bottom is Puxiao; the substance floating on top is Mangxiao. Those with crystalline teeth-like structures are Mayaxiao (Horse-tooth Saltpeter). Placed in wind and sun until moisture evaporates, becoming light and white like powder, it is called Fenghuaxiao (Weathered Saltpeter). Dahuang is used as an guiding herb. (Bencao Bie Lu notes that although Puxiao and Xiaoshi are classified as two different substances, their flavors, properties, and indications are roughly similar. Later discussions were controversial without definitive conclusion. Li Shizhen stated: Puxiao descends, belongs to Water nature, and is cold; Xiaoshi is used to manufacture explosive saltpeter, ascends, belongs to Fire nature, and is warm.)