Introduction of Chan Tui:Periostracum Cicadae or Cicada Slough.
✵The TCM herbalism is also known as pharmaceutics of Traditional Chinese Medicine, or Chinese pharmaceutics, is the branch of health science dealing with the preparation, dispensing, and proper utilization of Chinese herbs. It is majorly composed of Introduction of Chinese Medicinals, Classification of Chinese Herbs, Formulas, and Patent medicines.
Classifications of Herbs:Pungent-cool Exterior-releasing Herbs.
Introduction: Pungent-cool exterior-releasing herbs: an agent or substance herbs pungent in flavor and cool in property, which is usually used for treating a wind-heat exterior syndrome.
✵Till the date Oct 10th,2019, there are totally  kinds of common TCM herbs,  kinds of related plant species,  kind of insect species, are recorded in this category. These pungent-cool exterior-releasing herbs are briefly introduced separately:
Periostracum Cicadae(Cicada Slough).
Pin Yin Name: Chán Tuì.
English Name: Cicada Slough.
Latin Name: Periostracum Cicadae.
Property and flavor: cool, pungent.
Brief introduction: The herb Periostracum Cicadae is the slough shed by the nymph of Cryptotympana pustulata Fabr.(family Cicadidae), used (1).to disperse wind and heat in the treatment of wind-heat affliction, (2).to promote eruption for measles and relieve itching for urticaria, (3) .to remove the nebula and improve eyesight, and (4).to relieve spasm in infantile convulsion and tetanus.
Botanical source: The herb Periostracum Cicadae(Cicada Slough) is the slough shed by the nymph of Cryptotympana pustulata Fabr., it is an insect of the Cicadidae family of the Hemiptera order. It is also known as Periostracum Cicadae, Cicada Slough, Chán Tuì.
Common official herbal classics and other famous herbal classics defined the herb Periostracum Cicadae(Cicada Slough, or Chán Tuì) as the slough shed by the nymph of (1). Cryptotympana pustulata Fabr. This commonly used species is introduced as:
(1).Cryptotympana pustulata Fabr.: Description of the Insect: It is also known as black cicada. Large black and shiny body; The male is 4.4~4.8 cm long with a wingspan of about 12.5 cm, while the female is slightly shorter. 1 pairs of compound eyes, large shape, there are 3 single eyes between two compound eyes, 1 pair antennae. The mouth is well-developed, spines and suckers, the labial base is comb-like, the upper lip is wide and short, the lower lip is elongated into a tube, up to the base of the 3rd pair of feet. The chest is well-developed, with a prominent cone-shaped protuberance on the posterior thoracic abdominal plate, extending backward. 3 on foot. 2 pairs of wings, membranous, dark brown, translucent, base stained yellowish-green, wings stationary when covered in the back as a ridge. The total abdominal volume of 7 sections, the abdomen of the male cicada has a special articulation organ, the female cicada has the same part.
Ecological environment and Habitat: the insect lives on trees of poplar, willow, elm, locust, and maple. It takes 12 to 13 years to pass through a generation. Resource distribution: it distributes in most areas of south China.
Growth characteristics: The adult insect mostly lives in the willow, the maple, the poplar, the apple tree, the pear tree, the peach tree, the apricot tree, and so on broadleaf trees. It is mainly produced in the lower reaches of the Yangtze River in China.
Characters of herbs: The whole herb looks like cicada and hollow, slightly curved. It is about 4 cm long and 2 cm wide. The surface is yellowish-brown, translucent and shiny. The head has 1 pair of filamentous antennae, many of which have been broken off. The compound eyes are prominent, the apex of the neck is prominent, the muzzle is developed, the upper lip is wide and short, and the lower lip is elongated into a tube. The reverse side of the chest was a cruciform lobe, the rift curled inward, the dorsal side of the spine with 2 pairs of small wings; the ventral surface has sufficient 3 pairs, by yellow-brown fine hair. The abdomen is blunt and round, with 9 segments. The body is light, hollow and fragile. No smell, light taste.
Pharmacological actions: The extract of this herb has anticonvulsant, sedative, antipyretic, anti-allergic, immunosuppressive, and analgesic effects. In vitro it can selectively inhibit the growth of cancer cells.
Medicinal efficacy: Dispel wind and dissipate heat, open the inhibited lung-energy, antispasmolysis, promoting eruption to relieve itching, removing nebula for improving eyesight, indicated for exogenous wind-heat affection, coughing and hoarsen, the poor eruption of measles, urticaria and itching, convulsive epilepsy or frightened epilepsy in children, red eyes, nebula, furuncle and malignant boils, tetanus.
Administration of Periostracum Cicadae(Chán Tuì):
Administration Guide of Periostracum Cicadae(Chán Tuì)
Internally:3~6 grams(CP), or 1~2 qian(about 3~6 grams),or prepare to pill,powder.Externally:wash with water decoction,or grinded into fine powder and apply stick(DCTM), or 3~6 grams, or prepare to pill,powder.Externally:proper amount,wash with water decoction, or grinded into fine powder and apply stick(CHMM), or 3~10 grams, water decoction, take after mixing its fine powder with water or wine, big dosage needed for relieve spasmolysis.
1.Introduction of Chan Tui:Periostracum Cicadae or Cicada Slough.
2.TCM Books:DCTM(Dictionary of the Chinese Traditional Medicine),CHMM(Chinese Herbal Materia Medica).