Psychological Aspects of Coca Addiction


Although coca addiction or the habit of chewing coca leaf is a social problem which in practice affects mainly Peru and Bolivia, it is now being studied by the United Nations Department of Social Affairs because it is related to the production of the raw material from which cocaine, a narcotic drug subject to international control, is extracted.


Author: Martín Cárdenas
Pages: 6 to 9
Creation Date: 1952/01/01

Psychological Aspects of Coca Addiction

Dr. Martín Cárdenas
Professor of Genetics and Economic Botany, Faculty of Agronomic Sciences, University of Cochabamba

Although coca addiction or the habit of chewing coca leaf is a social problem which in practice affects mainly Peru and Bolivia, it is now being studied by the United Nations Department of Social Affairs because it is related to the production of the raw material from which cocaine, a narcotic drug subject to international control, is extracted.

Much has been written about the effects of cocaleaf chewing on the organism of the indigenous inhabitants of Peru and Bolivia, and there is an open controversy between those who condemn this practice as a dangerous vice and those who defend it, not so much because it is a valuable element of diet at high altitudes - which is very doubtful - as because it is a century-old custom which cannot be eradicated so long as the living conditions of the population remain as they are today.

In explanation of the existence of these two diametrically opposite positions, it may be said that addiction to cocaine, the extracted alkaloid is one thing and that coca-leaf chewing as practised by the Indians is quite a different matter. Cocaine addiction is a universally condemned vice of the white race, while the custom of coca chewing has not yet been condemned on the basis of conclusive scientific findings. In this connexion, we might recall the opinion of the distinguished Peruvian physician, Dr. Carlos Monge, who, in commenting on the United Nations Commission's report on the use of coca, called attention to the complexity of the problem and the need to study it more thoroughly.



The European who comes to Peru and Bolivia and observes the indigenous population, not unnaturally bears in mind a picture of the degradation of the white cocaine addict. In these Andean countries he sees a possibly even more striking picture: Indians leading a miserable existence and chewing coca as ruminants chew their cud - a spectacle not likely to please the white visitor's refined taste.

We do not know at what period the American Indians first brought the coca plant under cultivation, any more than we know when they first used tobacco and peyote (Lophophora). We are equally ignorant concerning the domestication of the poppy, betel and Indian hemp of Asia and Africa. It would appear that only the continent of Europe has no native plants from which narcotic drugs are produced. The alka- loids include some of the poisons most dangerous to man as well as some of the most potent drugs. It is not yet known what purpose these alkaloids serve in the plants which produce them, although it is thought that, being bitter to the taste, they perform a defensive function.

Substances containing alkaloids have been used from the very earliest times for chewing and smoking the world over, either for pleasure, or for some physiological effect, or in connexion with religious ritual. The vegetable substances which are chewed or smoked have a disagreeable taste, and yet man uses them eagerly. Animals would reject such substances, which incidentally have no food value. It would appear that man's nervous system has reached a certain degree of development which enables him to enjoy chewing and smoking substances containing alkaloids. Man's eternal struggle against a hostile environment must have developed in him psychological states of depression, which are regarded as the reason for the consumption of alkaloid-containing plants producing mildly stimulating or euphoric effects. The extraction of these alkaloids in modern times has made it possible to use them therapeutically, in much stronger doses and with much more pronounced effects. It would seem in general that addiction to alkaloids has a largely psychological basis and presupposes a certain degree of development of the nervous system.

The place of origin of the coca shrub (Erythroxylon coca) has not been definitely determined, but it is probable that it was cultivated on the eastern slopes of the Andes, long before the formation of the Inca Empire, under conditions similar to those existing today in the Yungas region of Bolivia. According to Rusby, Erythroxylon coca is very close to the forest species Erythroxylon anguifugum, but is actually a garden species, that is to say a form which has been cultivated so long that it has acquired the status of a species. According to the same author, the Peruvian or Trujillo coca which he calls Erythroxylon truxillense Rusby, is a different species from Erythroxylon coca Lam., or the Bolivian and Huanuco coca. Mr. Genter, who is now studying the toxonomy of the cultivated species of coca, maintains that the Rusby species is identical with Erythroxylon coca and that Erythroxylon novogranatense (Morris) Hieron. is also closely related to Erythroxylon coca, although it is sufficiently differentiated to be entitled to specific distinction. Most of the various species of Erythroxylon come from the lowlands of eastern South America, Brazil and the West Indies. In Rusby's judgment, if Erythroxylon coca is closely related to the Brazilian forest species, Erythroxylon anguifugum Mart, it may be assumed that the coca cultivated in Peru and Bolivia comes from Brazil and Colombian coca from the West Indies.

According to Juan de Matienzo, Judge of the Royal High Court (Audiencia) of Charcas, who wrote a history of Peru towards the end of the sixteenth century and who is mentioned by Carl O. Sauer, the cultivation of coca was confined to the warm valleys of the Andes between Guamanga and Sucre and the leaves harvested were reserved for the Inca. According to the same Spanish jurist, control of the use of coca was abolished after the Spanish Conquest, and as a result its cultivation spread to other areas.

Henry H. Rusby, an American doctor and a great expert on South American economic plants who for many years was Dean of the College of Pharmacy of Columbia University in New York City, was sent to South America by the firm of Parke Davis to study the effects of coca on the natives and the possibility of introducing it into Europe and the United States in the form of elixirs and other preparations. Rusby arrived in Bolivia in 1885 and spent several months in the Yungas region near Coroico, armed with some equipment for the chemical analysis of vegetable drugs. At that time he arrived at a very interesting conclusion, which is that fresh - in other words, recently harvested and dried - coca was a very different drug from the coca which reached Europe after many days of travel by land and sea, inasmuch as the two types of coca had different cocaine and other alkaloidal content, owing to the processes of disintegration and reconstitution of those compounds which were caused by the passage of time.

Presumably, those processes occurred in the following cycle: cocaine into cocaicine or cocainoidine into benzol ecgonine into ecgonine into cocaine. This judgment cannot be borne out by our present knowledge of the disintegration cycle of coca alkaloids. A noteworthy feature of Rusby's writings are his observations on the wonderful effects attributed to the coca plant by the Indians of the Andes, who used a residue of coca leaf from which cocaine had already been extracted. His experience led him to think that the highly exaggerated effects of coca, such as endowing the chewer with resistance against hunger and altitude, were due not to cocaine but to other alkaloids. Even granting that the effects of coca were due to cocaine, Rusby pointed out that it was not yet fully known what specific effect that alkaloid had on the human body.

With regard to the effects of coca-leaf chewing on the Bolivian Indians, Rusby says:

"The great difference between native coca and other drugs of its class is that its effects do not greatly diminish with continued use. What it does for the Indian at fifteen it does for him at sixty, and a greatly increasing dose is not resorted to... I myself mixed for nearly a year among a million people who use coca daily without ever seeing a single case of chronic cocaism, although this one subject chiefly occupied my attention, and I searched assiduously for information... These people have been described as 'weak, puny, and intellectually little above the beast'. So far as this applies, it is a race peculiarity, and it is the more remarkable that such people should perform daily tasks during long lives which would quickly destroy our finest athletes."

My personal observations in Bolivia indicate that habitual coca chewing is confined to the Indian and mestizo (half-breed) classes, although native whites occasionally have recourse to it in special circumstances. During the Chaco War, coca chewing among the mestizo and white Bolivian soldiers was widespread. I have experienced its beneficial effects myself in forced marches on mountain roads at high altitudes. It was formerly customary for secondary school pupils to chew coca leaf when studying for their annual examinations, as the drug was thought to stimulate the mind's powers of assimilation. The infusion of coca as a home remedy against stomach ache is still very popular. Coca really has a disagreeable taste, which, I believe, is the reason it has not been used industrially for the preparation of gaseous beverages and digestive elixirs. Dr. Rusby says that in 1885 coca elixirs to be taken after the evening meal were widely sold. in the pharmacies of La Paz.

The Indians chew coca leaf with a special paste made of ash, known as llukta, while some mestizos and whites add bicarbonate of soda instead. Those two substances may help to liberate the alkaloids while the wad of coca, which is subjected to sucking for a long time, is gently chewed and impregnated with saliva. Dr. Rusby, on the other hand, believes that the ash is used only in order to improve the taste of the coca, even as salt is used in ordinary food. With reference to the taste of the coca chewed, I have observed in some villages along the upper reaches of the Beni River, that the Indians, after chewing a few leaves of coca, chew a kind of liana called chamairo, which has not been botanically identified, and immediately afterwards put powdered ashes into their mouth. In these conditions, the coca is said to have a sweetish taste.

The nutritive value attributed to the coca leaf because it greatly sustains the strength of Indians who live over 3,500 metres above sea level on a diet poor in vitamin content is non-existent and the legend is due to a failure to understand the process of assimilation. The use of coca is not always related to altitude, since there are people, like the Ecuadoreans, who do not chew coca although they live at great altitudes, while in Bolivia there are groups in the Amazon region who chew coca although they live at an altitude of only 200 metres.

In explanation of the power to dispel hunger and thirst, which is attributed to the coca, Dr. Rusby has the following to say:

"A portion of the results here considered are doubtless due to its anaesthetic effect on the stomach. The exhausting effect of hunger, and consequently of labour accompanied by hunger, is not wholly due to a lack of nutrition. The first evil is the nervous waste produced by the endurance of hunger's pangs... These pangs are absolutely allayed by the use of coca leaves. It allays hunger and thirst completely, and thus supports the traveller by removing the chief source of his fatigue. This is a most important action; but I believe that in no other way can the drug be considered as a 'preventer of waste', as we so frequently hear it called. The expenditure of force is possible only by the consumption of energy, and energy implies waste. But through bad nervous conditions energy may be consumed without the production of any useful force. This loss coca tends to check... Thus, by alleviating pain, it leaves the system free to secure the utmost benefit from vital action."

Let us now turn to the psychological aspects of coca chewing, which derive largely from the fact that, as maintained by Rusby, coca deadens hunger and thirst as nervous manifestations, and that its action also extends to higher psychological phenomena, such as the emotions. Let us begin by visualizing the evolution of the indigenous peoples of South America from primitive nomads gathering roots and fruits from the forests to tribes settled in the mountainous regions of the Andes with a highly advanced agriculture.

It is probable that the successive waves of Mongols who migrated from Asia to America some 10,000 years before the Christian era and who belonged to a late Paleolithic culture crossed the continent from north to south and from east to west and came to settle on the banks of tropical rivers where they learned to cultivate maize and other tropical plants. The need for fish and the universal human instinct for adventure probably impelled those early Americans to explore the rivers up and down stream on rafts and in canoes. Adventuring towards the upper part of the tributaries of the Amazon meant freedom from the heat, wild beasts and insects, and resulted in a move to regions which, owing to the altitude, were more temperate, although unwooded. The valleys of the Urubamba and Apurimac in Peru, with their fertile soil, mild climate and many forest plants which could be brought under cultivation, probably represented the last stage in the evolution of these tribes, endowed with great enterprise and highly developed intelligence. These men, who had come from the forest, probably settled down in these regions with the cultivated plants that they had brought from the lowlands, such as maize, porotos (a kind of pea), cassava, peanuts, etc., in addition to which they brought under cultivation potatoes and other minor tubers, such as the quinoa. Later still, either these same groups or others who came down from Central America or Mexico presumably reached the northern coast of Peru. This would account for the original settlement of the future builders of the great civilizations of Mochica and Chimú along the coast and of Tihuanacu on the shores of Lake Titicaca. The ancient civilizations of the Old World were founded on an agriculture which consisted largely of the cultivation of cereals, more particularly of wheat, as in the case of Assyria, Babylon and Egypt. Similarly, the civilizations of Mexico, Central America and Peru were able to rise only after the cultivation of maize had become widespread. It may be of interest to note that the best arable lands tilled in the United States and Argentina today were not utilized by the ancient Indians, possibly because the basic agricultural products of the great American civilizations were vegetable species requiring a short day and unsuited to the latitudes in which species imported from Asia and the Mediterranean regions, with their long hours of daylight, are cultivated today and produce remarkably high yields.

The great South American cultures of the Peruvian coast and Tihuanacu indicate a high degree of mental development. As proof of this statement, we may point to the amazing stone constructions of Machupicchu, Saxahuaman, Pissac, Ollantaytambo, Tihuanacu, etc., to the development of an advanced agriculture with a great many varieties of corn and potatoes such as modern agronomy could not produce, and the construction of vast terraces for the conservation of good soil. That being so, it may well be asked what caused the fall of these advanced civilizations of which nothing remains but architectural monuments, the ruins of their cities, temples and tombs in the midst of a solitude barely if at all disturbed by the presence of the Indians of our day, sunk in apathy and indifference which make one despair that they can ever become part of modern life.

When the cultures of the coast and interior of ancient Peru were nearing their peak, the minerals in which the Andes in that region of South America abound, that is to say, copper and tin, were discovered. The metallurgical era, which is synonymous with modern civilization, began in South America, but it could not develop there because the highlands lacked fuel resources. The lack of coal was the tragedy of the entire continent, from Mexico to its southernmost tip. Because the minerals could not be smelted in South America, the cultures described above were checked and started rapidly on a downward course. It may well be that the Collas or their ancestors who erected the great monuments which we admire today were aware of their fate and experienced a profound frustration which has left a lasting imprint on the race and accounts for the sadness, apathy and indifference of present-day Indians.

These brief remarks are intended to show the Indian of the Andes not as a man degraded by the vice of coca chewing, but as an unhappy, disillusioned human being robbed of his destiny and made helpless by the lack of natural resources with the aid of which he might have covered the stages that separate him from the level of modern civilization. As we gaze at the passive Indian chewing his coca leaf in his moments of rest or when engaged in the hard manual labour required for mining and agriculture, we feel that he is at the same time meditating on his tragic fate by remembering his past, analysing his present and catching glimpses of his future. Coca chewing is a delicate rhythmic process, in the course of which the Indian chooses one by one the leaves which bring him solace and inserts them into his mouth in a reflex gesture conditioned by his emotional associations, even as the white smoker takes a cigarette from his pocket with joyful anticipation, lights it, inhales the smoke and watches it dissolve in the air, in moments of emotional well-being or depression. The Indian practically never smokes when he chews, while white men smoke most when taking coffee or spirits.

In conclusion, I wish to say that I do not regard as proved the assertion that the Indian's state of mental prostration is the result of coca chewing. Nearly five centuries have elapsed since the Spanish Conquest; in all that time the Indians have gone on chewing coca and yet their mental level does not appear to have been lowered. The use of cocaine for other than medical purposes is to be condemned, but, until I have been proved wrong, I shall not believe that coca chewing is as dangerous as it is said to be. The observer is impressed largely by the fact that it is an ugly and filthy habit.

I believe that the production of coca in Peru and Bolivia should be placed under control primarily in order to prevent clandestine extraction of cocaine in the absence of international provisions governing either the cultivation of or trade in the raw material.


Henry H. Rusby. "Coca at Home and Abroad", The Therapeutic Gazette for March and May, 1888 Detroit, Mich

George S Davis, Publisher Jungle Memories McGraw-Hill, New York, 1933.

Bureau of American Ethnology Handbook of South American Indians, vols. II and VI 1946 and 1950, Washington, D C

Hill Economic Botany, McGraw-Hill, New York, 1937.

Cushny, A R Pharmacology and Therapeutics Lea and Febiger, 1936

United Nations Bulletin on Narcotics, no 1, October 1949, and vol II, no 4, October 1950