Zhang Nao樟脑
Camphora · Camphor
Overview
- ·.*
The crystalline substance distilled from the wood of the camphor tree — acrid, hot, penetrating and toxic. Rubbed on the skin it dries damp, kills the organisms of ringworm and scabies, relieves itch, and warms and numbs a painful bruise or joint; the classical texts also used tiny internal doses to rouse someone from sudden collapse. Camphor is a familiar household smell, which is exactly the problem: it is readily absorbed through skin and mucous membrane, it is a nerve poison in overdose, and small children have died from swallowing amounts that look trivial. In practice it belongs in a compounded topical preparation and nowhere else.
Nature & Flavor
Acrid · Hot · ToxicChannels
Heart · SpleenTypical Dosage
0.1–0.2 gActions
4 core actions
- Dries damp, kills parasites, stops itchRingworm and tinea of the foot, scabies, itching damp eruptions and chilblains — the mainstream use, always topical.
- Warms, disperses and relieves painBruises and sprains, cold damp aching joints, and toothache — applied over the painful place, where it produces the familiar cooling-then-warming sensation.
- Opens the orifices, dispels turbidityThe classical internal use in sudden collapse with cramping abdominal pain, vomiting and diarrhoea. It is recorded here as history; the dose is minute and the margin is poor.
- Absorbed through the skinCamphor passes readily through skin, especially broken or inflamed skin, and through the lining of the nose. Enough of a strong preparation on a large area can poison, and the same is true of the ointments sold for colds when they are used on infants.
In Formulas
Formulas containing Zhang Nao
No published formula lists this herb yet — the library is growing.
Indications & Clinical Uses
- Ringworm, athlete's foot and scabies (external)
- Itching damp skin eruptions and chilblains (external)
- Bruises, sprains and cold damp joint pain (external)
- Toothache, applied locally
- Sudden collapse with cramping and vomiting (classical internal use, obsolete)
Western Medical Keywords
Searchable condition terms
Contraindications
Cautions
Camphor is toxic, and it is a nerve poison. Swallowing it causes burning in the mouth, nausea and vomiting, agitation, confusion and seizures; in small children a quantity of only a gram or two has proved fatal, and poisoning has also followed heavy application to the skin. Do not take it internally. Keep camphor preparations, including the familiar chest rubs and mothball-type products, locked away from children. Never apply it to the nostrils or face of an infant or young child, never to broken, burned or widely inflamed skin, and never under an occlusive dressing over a large area. It is contraindicated in epilepsy and in anyone with a history of seizures, and in liver impairment. Stop at once and seek medical care if agitation, confusion, twitching or vomiting follows use. Accidental ingestion, at any age, is a medical emergency.
Contraindicated in pregnancy: Contraindicated in pregnancy — camphor crosses the placenta; avoid while breastfeeding, and never apply it to the breast area.
For licensed practitioners’ reference only
References
- Ben Cao Pin Hui Jing Yao《本草品汇精要》(classical source, public domain).
2. Bensky, Clavey & Stöger. Chinese Herbal Medicine: Materia Medica, 3rd ed.
3. 《中华人民共和国药典》.
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.