1. Plant Name: Dokudami

2. Scientific Name: Houttuynia cordata Thunb.

3. English Name: lizard tail, chameleon plant,
heartleaf, fishwort, bishop’s weed

4. Alias: Gyoseiso

5. Family: Saururaceae Genus: Artemisia Houttuynia

6. Similar Western Herb: None.

7. Botany: A perennial widely found in Japan,
Taiwan, China, the Himalayas, and Java. Naturally grown in fields and gardens, blooms in June-July.
It is a perennial herbaceous plant which grows 15-30cm tall with broadly heart-shaped and alternate leaves. The flowers are borne on small short terminal spikes andfour white involucral scales underneath look like petals
of flower. Whole plant has a distinctive odor. (app.1)

8. Parts for Use: aerial parts in flower season

9. Crude Drug Name: Juyaku (十薬[shí yào]、重薬) (app.2)

10. Five Flavours, Four Natures: acrid, slight chill (app.3)

11. General Remarks: Its white flowers in clumps are very common in any damp shade. The leaves have characteristic odor. “Yamato Honzo”(encyclopedia on medicines in Edo-era) says this plant “has 10 different advantages so it’s called Juyaku which literally means 10 medicines”. In Traditional Chinese Medicine, it is used for detoxification, relief of edema, relief of fever, balancing water metabolism. As folk remedies, its infusion has been drunk for acne, nasal inflammation, eczema, constipation, and the fresh leaves have been used externally also. It is one of the most popular herbal teas in our time. The distinctive perfume comes from decanoyl acetaldehyde. Since the odor disappears when it dries and the dried herb does not have an aroma. The antibacterial activity of the aldehydes of fresh leaves (app.4)(app.5) and the antibacterial, anti-inflammatory, diuretic blood capillary enhancing activities in dried leaves (app.6)(app.7) are under study.

12. Chemical components:
Dried leaves: flavonoids (quercerin, isoquercitrin, afzerin, hyperin, rutin) (app.7)
Flesh leaves: flavoinoids (quercerin, isoquercitrin, afzerin, hyperin, rutin), decanoyl acetaldehyde, lauryl aldehyde (app.8)

13. Medicinal Uses:
Against water retention, inflammation, constipation, chronic dermatological conditions.(app.2)

14. Mode of Use:
One day dose is 10-15g of dried leaves. To be simmered with 600ml of water and drunk 3 times a day either before or in between meals. (app.2)

15. Safety:
Developing allergic dermatitis by drinking the infusion for 2-3 months and photosensitivity by drinking the infusion 1L a day for 2-3 years are reported. (app.10)

APPENDIX
1. Okada, Minoru. ed. 2002. “Makino Japanese and Chinese Medicine Pictorial Book” （『牧野和漢薬図鑑』Makino Wakanyaku Zukan）, Hokuryu-sha.
2. Society of Japanese Pharmacopoeia ed. 2006. “The Japanese Pharmacopoeia XV”, Hirokawa Shoten.
3. Namba, Tsuneo. ed. 2002. “Dictionary of Japanese Chinese Medicine”（『和漢薬の事典』）Asakura Shoten.
4. Isotani. et al. Saitama Medical University College Bulletin 2005;16:43-46,
5. Hiraga. et al. Saitama Medical University College Bulletin 2003;14:1-6,
6. Li. et al. “Pharmacognosy Magazine” (『生薬学雑誌』Shoyakugaku Zasshi) 1993;47(4):415-419,
7. Kawamura. et al. “Pharmacognosy Magazine” (『生薬学雑誌』Shoyakugaku Zasshi) 1994;48(3):208-212,
8. Fuse. et al. “Pharmacognosy Magazine” (『生薬学雑誌』Shoyakugaku Zasshi)1994:48(4):307-311
9. Yoshioka. “Dermis”（『皮膚』Hihu）1992; 34:271
10. Takahashi. “Dermatitis Practice”（『皮膚病診療』Hifubyo Shinryo）1985; 7:21-24