Chan Tui
Cryptotympana pustulata Fabricius
☯ TCM Properties
Disperses Wind-Heat; Benefits the Throat and Restores the Voice; Vents Rashes and Stops Itching; Brightens the Eyes and Removes Visual Obstructions; Extinguishes Wind and Stops Spasms
Botanical Description
Chan Tui is not a plant but the dried cast-off exoskeleton (exuvia, or slough) shed by the nymphs of cicadas, principally Cryptotympana pustulata and related species in the family Cicadidae. After several years underground feeding on root sap, the final-instar nymph emerges, climbs onto a tree trunk or stem, and splits its old exoskeleton down the back to allow the winged adult to emerge; the empty cuticle remains clinging to the substrate and is collected as the medicinal material. The slough is a thin, fragile, translucent yellow-brown shell about 2-3 cm long, retaining the segmented body shape with intact head, prominent compound eyes, six clawed legs, and a longitudinal dorsal split (Wikipedia; NCBI).
Dosage
| Form | Amount | Frequency | Duration | Population | Notes |
|---|---|---|---|---|---|
| decoction | 3-9g | Daily | — | — | — |
Cultural & Historical Context
Traditional Chinese Uses
Zhu Dan (pig bile) is a cold, bitter substance used to clear internal Heat, moisten dry intestines, and resolve toxins. It is most recognized for treating constipation from fluid depletion, chronic cough and wheezing from heat-dryness, sore throat, and red, inflamed eyes. Its historical significance is substantial — it features in Zhang Zhongjing's Shang Han Lun as both a topical enema for constipation and as an ingredient in formulas for critical Yang-collapse conditions.
Traditional American Uses
None Documented
Important Disclaimer
This information is for educational purposes only and is not intended to replace professional medical advice. Always consult a qualified healthcare provider before using any herbal remedy, especially if you are pregnant, nursing, or taking medications.