Pi Shuang砒霜
Arsenicum Sublimatum · Sublimed Arsenic Trioxide · White Arsenic
Overview
- · — appended to Pi Shi 砒石.*
What you get when Pi Shi is sublimed: a white, almost pure arsenic trioxide powder, with the impurities of the crude mineral removed. Its nature, channels and classical actions are the same as Pi Shi's, and so is the dose — the only thing that changes is that the purification makes it stronger and more predictable, which in a poison means more dangerous, not more useful. It is the substance that Chinese history and fiction simply call 'the poison', and its reputation there is earned. Internal use is obsolete. What is written here is the classical record, kept alongside its parent entry because the textbook lists it there; it is not a treatment recommendation, and the crude substance is prohibited across most of the world.
Nature & Flavor
Acrid, sour · Very hot · Strongly toxicChannels
Lung · LiverTypical Dosage
0.002–0.004 g a day internally, in pills or powder — recorded from the classical literature, obsolete, and not to be attempted. External use in a very small heavily diluted amount on the lesion alone. Never with alcohol.Actions
4 core actions
- Eats away dead tissueThe same external role as Pi Shi — haemorrhoids, gangrenous gums, ulcers whose slough will not separate — with the purified powder acting faster because there is more arsenic per grain.
- Attacks toxinChronic toxic sores in the classical external record.
- Cuts through cold phlegm wheezingThe internal use inherited from Pi Shi, for entrenched cold-phlegm asthma. Obsolete, and the purity of this form makes an error in weighing correspondingly less survivable.
- Purity is the danger, not the meritThe crude mineral is variable; the sublimate is not. In a therapeutic drug, consistency would be an advantage. In a substance whose lethal dose is measured in tens of milligrams, it means the margin that variability accidentally provided is gone.
In Formulas
Formulas containing Pi Shuang
No published formula lists this herb yet — the library is growing.
Indications & Clinical Uses
- Haemorrhoids, gangrenous gums, sloughy ulcers (classical external use, heavily diluted)
- Chronic toxic sores (classical external use)
- Cold-phlegm wheezing (classical internal use, obsolete)
- No part of this entry describes current practice
Western Medical Keywords
Searchable condition terms
Contraindications
Cautions
Pi Shuang is refined arsenic trioxide — strongly toxic, cumulative, and a recognised human carcinogen. Every caution under Pi Shi 砒石 applies here with less margin. Read this entry as a record of the classical materia medica, not as a treatment recommendation.
- Acute poisoning is the same picture and comes on faster: burning throat, violent vomiting, watery diarrhoea, collapse, seizures, and death from multi-organ failure within hours to days. Human lethal doses are measured in tens of milligrams.
- Chronic poisoning — palm and sole keratosis, patchy pigmentation, white nail lines, painful peripheral neuropathy, anaemia, liver and kidney injury — follows repeated small exposures, including topical ones.
- Cancer. Arsenic is classified as carcinogenic to humans; long exposure raises the risk of skin, lung and bladder cancer.
- Absorbed through broken skin. Never treat more than a small lesion, never for more than a very short course, never on mucous membranes, and never on more than one site at a time.
- Dose ceiling. The classical internal limit is 0.002–0.004 g a day. It is recorded, not recommended. There is no acceptable self-directed use.
- Never with alcohol. Classical incompatibility: — arsenic and mercury preparations are not combined.
- Absolutely avoided in pregnancy, breastfeeding, children, liver or kidney impairment, and debility.
- Storage and handling are a safety matter in their own right. It is a white, odourless, tasteless powder that has been used to kill people for two thousand years. If it exists in a dispensary at all, it is labelled, locked, logged and kept nowhere near anything edible.
- Legal status. Arsenic-containing medicines are prohibited or tightly restricted in the EU, the UK, the US, Canada and Australia. Supply of this substance is generally unlawful for a practitioner outside China.
- Hospital arsenic trioxide is a separate thing. The approved ATO infusion used in acute promyelocytic leukaemia is a purified, assayed, dose-controlled pharmaceutical given under oncology supervision with cardiac monitoring. That indication says nothing about the herbal use of this powder.
Contraindicated in pregnancy: Contraindicated in pregnancy and while breastfeeding — arsenic crosses the placenta and passes into breast milk, and it is toxic to the developing fetus. There is no safe amount.
For licensed practitioners’ reference only
References
- Pi Shuang is recorded in the Chinese materia medica as the sublimed form of Pi Shi; the first source text is not asserted here.
2. Bensky, Clavey & Stöger. Chinese Herbal Medicine: Materia Medica, 3rd ed.
3. 《中华人民共和国药典》(the arsenic dose limits and the external-use restriction).
4. The International Agency for Research on Cancer classifies arsenic and inorganic arsenic compounds as carcinogenic to humans (Group 1).
5. Arsenic in medicinal products is prohibited or restricted in most Western jurisdictions — confirm the current position with your own regulator.
Professional reference notice. Entries are scholarly references for licensed TCM practitioners and students — not medical advice, and not a recommendation to self-prescribe. Chinese herbal formulas should be used under the guidance of a qualified practitioner. Content is an original editorial compilation by Cura x Cura, cross-checked against the cited references.