Characterization and Physiological Activity of Some Kawa Constituents 
R. Hansel 1 
Kawa , the rhizome of Piper methysticum, has 
played an important role in the lives of the 
peoples of Oceania. This paper presents a re- 
view of our current knowledge of the kawa 
constituents — their molecular structure, their 
pharmacological properties, and their chemical 
and spectroscopic character. 
AROMATIC CONSTITUENTS AND THEIR 
PHYSIOLOGICAL ACTIVITY 
Piper methysticum Forster is a shrub in the 
family Piperaceae which occurs in Oceania. Its 
striking characteristics are long-stemmed, heart- 
shaped leaves, peculiarly knotty branches, and 
small flowers which lack a perianth and which 
form a dense inflorescence reminiscent of ears 
of grain. It is one of the bisexual members of 
the genus; apparently, however, only plants with 
male flowers exist. This necessitates vegetative 
propagation of the species. The original habitat 
of the plant is not known; perhaps it is New 
Guinea. From the rhizome, less often from a 
sprout, Polynesians and Melanesians prepare 
the so-called kawa, ’ awa , or yangona drink, 
which is characterized by its peculiar sedative 
and muscle-relaxing effects. In order to under- 
stand the role which the kawa plant played in 
the life of these peoples one has to consider 
the endemic character of the flora of these 
regions. The flora of Oceania is markedly differ- 
ent from that of the Asian continent as well as 
from that of the American continent. Nature 
did not provide the Polynesians with intoxicants 
and stimulants of plant origin, substances of the 
types which were known to the peoples of Asia, 
Europe, and America. Most of the indispensable 
medicinal agents — such as opium, hashish, coca 
leaves, the Solarium drugs, digitalis, and Col- 
chicum — of the peoples of the old world and 
of the American continent remained unknown 
to the Polynesians. Nor did they have alcohol. 
1 Institute of Pharmacognosy, Freie Universitat 
Berlin, West Germany. Manuscript received June 13, 
1967. 
They knew only one stimulant which at the 
same time was an effective medicine: ’awa. Ap- 
parently, ’awa for the Polynesians was a stimu- 
lant, an anesthetic, and an effective medicine. 
A plant of such importance, of course, also 
played a role in the religious life: kawa was the 
drink at religious ceremonies. 
If one summarizes the numerous reports in 
the ethnological literature about the folk medi- 
cinal uses of the drug and translates them into 
modern scientific language, the following 
striking properties of kawa emerge (Lewin, 
1886; Titcomb, 1948; van Veen, 1938): (1) 
It removes tension and anxiety. (2) It is an 
analgesic. (3) Small doses relax the muscles of 
the extremities, while larger doses paralyze 
through relaxation, without, however, causing 
a decrease in consciousness or will power. (4) 
The reversible relaxation or paralysis of the 
muscles of the extremities is not as pronounced 
as it is with curare; it also probably acts on the 
central nervous system. (5) The drug is active 
against various skin diseases. (6) Consumption 
of kawa may lead to photophobia. 
Modern research has dealt with two major 
tasks: first, to recognize which constituents are 
responsible for the effects listed here; and 
second, to analyze the effects themselves through 
studies with experimental animals. The em- 
phasis in the following discussion will be on 
pharmaco-chemical considerations. Results of 
pharmacological investigations will be treated 
only parenthetically. 
The characteristic constituents of kawa 
If one chews a piece of kawa, the tip of the 
tongue quickly becomes numb, as if one had 
chewed coca leaves. All of the early investiga- 
tors associated kawa with cocaine, the local 
anesthetic principle of Folia cocae. This associa- 
tion, later shown to be false, directed kawa 
research into certain channels. First, a belief 
persisted until very recently that kawa must 
have nitrogenous principles (alkaloids) as does 
coca. Every so often a report appeared which 
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