Coca-paste smoking in some Latin American countries: a severe and unabated form of addiction
The coca paste syndrome
The four phases of mental disorder caused by coca-paste smoking
Health and social consequences of coca-paste smoking
Study of volunteers
Epidemiology of coca-paste smoking
Illicit supply and trafficking
Coca leaves, coca paste and cocaine hydrochloride: a comparative review
Factors behind the spread of coca-paste smoking
Treatment of coca-paste smokers
Author: F. RA?L JERI
Pages: 15 to 31
Creation Date: 1984/01/01
Professor of Clinical Neurology, University of San Marcos, Lima, Peru
Coca paste is an intermediary product in the chemical extraction of cocaine from coca leaves. Abusers smoke coca paste in a dried form, which contains from 40 to 91 per cent cocaine. Over the past 10 years, this pattern of drug abuse has attained epidemic proportions in some Latin American countries, particularly in Bolivia, Colombia and Peru. Addiction to coca paste develops in a few months and has serious health, social and economic consequences. The problem is particularly acute in Latin American countries because of the high doses of coca paste involved. The smoking of coca paste causes four distinct successive phases of mental disorder: euphoria, dysphoria, hallucinosis and paranoid psychosis. It can produce severe intoxication, prolonged or relapsing psychosis and, in some cases, death. Cocaine has been found in the blood of coca-leaf chewers, coca-paste smokers and users of cocaine hydrochloride. Excessive coca-paste smoking is often resistant to therapeutic interventions and there is a high rate of relapse after treatment and rehabilitation.
In 1972, Peruvian physicians were asked to examine young people who smoked cocaine paste, a practice that led to a compulsive need to repeat the experience  . Soon many paste smokers were being admitted to hospitals because of severe physical and psychological complications; some, indeed died from acute intoxication after consuming large amounts of the drug. It soon became apparent that there were many kinds of cocaine paste or basic cocaine paste but all were intermediate products of the illicit production of cocaine hydrochloride. Chemical analysis showed that cocaine paste contained cocaine sulphate, ecgonine, other coca alkaloids, benzoic acid, methanol, kerosene, sulphuric acid and alkaline bases. The paste was white or brown, depending on the proportion of cocaine and other constituents found in it  . As the paste was a mixture of several substances derived from chemical treatment of the coca leaves, it was considered more appropriate to call it "coca paste". The content of cocaine varied considerably from one sample to another, usually from 40 to 91 per cent[ 2] -  . Figure I shows a fruiting branch and young leaf of the coca plant from which the paste is derived, and figure II shows coca paste of the variety known to the laymen as crude basic cocaine paste.
Eight years ago the author and his colleagues  reported on coca-paste smoking by seven young people who also used other drugs. Two years later, this form of drug-taking had become much more widespread in Lima and it was possible to describe the physical and mental changes in 158 patients who were undergoing treatment in several psychiatric hospitals and clinics  ,  . Towards the end of 1978, a clinical study was presented at Toronto of 188 coca-paste smokers from four psychiatric hospitals  . Soon, several other medical groups reported cases of coca-paste smoking in Bolivia  , Colombia  and Peru  ,  ,  . In Peru, the coca-paste epidemic spread rapidly to the main cities and cases were found in all regions of the country. Coca paste was also seized from traffickers who had travelled to neighbouring countries  ,  .
The present article is based on a study of 348 patients, of whom 315 (90.5 per cent) were male and 33 (9.5 per cent) female. They were aged between 10 and 62 years, but approximately half of them were in the 10 - 20-year age group.
Some common characteristics were found among the smokers: there were more males than females, most were single, the majority began to use drugs when they were between 10 and 20 years of age, and they usually started to smoke paste after having tried other drugs. The majority of the smokers were secondary school pupils or university students, but at the time of the study most of them had already dropped out. All these young people had been admitted to medical care because coca-paste smoking had become a serious problem for their health or for their social adjustment. A considerable degree of dependence had usually developed in a matter of months  ,[ 6] ,  ,[ 14] .
The usual method of taking the drug is to stuff dried coca paste into the end of a tobacco or cannabis cigarette and twist the paper. The smoker then lights the cigarette at that end and takes deep, rapid puffs to permit combustion of the material and inhalation into the lungs. Coca-paste and tobacco cigarettes combined are smoked for pleasure. Many smokers said that they found no other drug provided the same pleasure and this may explain why, after a few smoking sessions, they usually took no other drugs except alcohol. Coca-paste and cannabis cigarettes combined are smoked for social purposes. This combination makes the users garrulous and sociable, and they enjoy company, dancing and music. They have to be very careful, however, because coca-paste can have unpleasant effects after a few cigarettes, so when they begin to feel stiff, shaky, anxious or dizzy, they have to drink alcohol to dispel the side-effects.
If the experience is repeated, users soon find that they want to smoke more cigarettes and at more frequent intervals. After a few seconds of intense euphoria, they become very anxious and want to smoke more. The next cigarette gives another high but soon this experience is replaced by numbness in the mouth, a burning sensation in the eyes, sweating, palpitations, twitching of the muscles, shaking limbs, headache, hyperactivity, dizziness, colic-like abdominal pains, and the desire to urinate or have a bowel movement. These feelings and motor disturbances can be alleviated by ingesting alcohol and for this reason, coca-paste cigarettes are usually smoked between alcoholic drinks.
If smoking continues, the user undergoes the following psychological changes:
Objects are seen as very large or very small;
Time seems to stand still or to pass very slowly or very quickly;
Shadows appear as dangerous objects;
Ordinary sounds become threatening noises.
Ultimately smokers may experience unpleasant visual, auditory, olfactory, cutaneous or genital hallucinations. These abnormal sensations are accompanied by delusions: for example, smokers may imagine that someone is trying to kill them or put them in gaol; that their husbands or wives are being unfaithful; or that they are being chased by animals, monsters or ghosts. They will then be held down by friends and made to stop smoking for a while or will be given more alcohol to drink, after which they will gradually calm down and then be able to go home. Often, smokers will stop smoking because the paste is all gone. At home they may then drink more alcohol or take a sedative in order to be able to sleep. The symptoms and signs of coca-paste smoking are set out in tabular form below. For more detailed information, see the earlier papers on the subject[ 2] ,  ,  .
Many people rapidly become compulsive users and begin to indulge in repeated smoking sessions, during which they exhibit four successive phases of mental disorder.
In the first phase, characterized by euphoria, the users experience excitement, affective lability, hypervigilance, hyperactivity, lack of appetite and insomnia and in a few cases hypersexuality. If the user carefully combines smoking with alcohol consumption, the state of elation can be maintained for a few minutes. Otherwise, he or she passes on to the second phase, characterized by dysphoria. The dysphoria develops very quickly, sometimes within seconds. A dysphoric state is manifested by considerable anxiety, smoking compulsion, sadness, apathy, melancholy, aggressiveness, sexual indifference, anorexia and insomnia. This stage can be ameliorated by smoking more coca paste, which helps the smoker to experience another pleasurable high.
|Symptom||Numberof cases||Percentage||Sign||Number of cases||Percentage|
The third phase is cocaine or coca-paste hallucinosis, which is characterized by visual, tactile, auditory and olfactory illusions and hallucinations, as well as delusional interpretation, psychomotor excitement, fugue tendencies, extreme suspiciousness, sexual indifference and sometimes aggressive acts. Hallucinosis usually lasts for a few hours or days. This disorder can be effectively treated by tranquillizers such as benzodiazepines or antipsychotic substances such as phenotiazines or haloperidol.
Some persons continue smoking for months or years, several times a week or every day, until they develop a persistent serious mental disorder, which the author terms "coca-paste psychosis". This is the fourth phase of mental disorder generated by coca-paste smoking. In this condition, the patient demonstrates hypervigilance, paranoid delusions, for example of persecution, injury, death, poisoning, witchcraft or infidelity, auditory and olfactory hallucinations, insomnia, and aggression, including attempted suicide, homicidal attack and sudden assault. In this state some smokers have died from an overdose, have committed suicide, or have been killed in an accident or during a fight.
If the psychotic patient is taken to hospital, conventional treatment, including detoxification, antipsychotic medication and psychotherapy, may bring about a recovery in a matter of weeks or months.
The different phases of mental disorder are associated with various physical disorders. During euphoria, dysphoria and hallucinosis the subject is usually thin, pale and shaky, sweats profusely, and has dilated pupils, high blood pressure, a rapid pulse, increased temperature and rigid muscles. Common complications are malnutrition, immunodeficiencies, dental, skin, respiratory, intestinal, hepatic and meningeal infection, tuberculosis, pneumonia and other respiratory disorders and cocaine-induced epilepsy.
Serious coca-paste intoxication can lead to indifference, inactivity, fever, lack of co-ordination, asthma, automatism, cardiac arrythmias, stupor, collapse, convulsions, neurogenic hyperventilation, respiratory arrest, cardiac arrest and death. The somatic and psychological disorders observed in the 348 coca-paste smokers under study when they were admitted to medical and psychiatric care are set out in tabular form below:
|Number of cases||Percentage||Number of cases||Percentage|
Coca-paste smoking has had a serious social impact on the patients under study. They have become so dependent on the drug that they have practically no other interest in life. They are inefficient at their jobs and experience marital problems, and the students fail courses or drop out of school. If they have a job, they are frequently absent from work because they do not feel well or because they spend time on procuring the drug. They need money to buy the coca paste, spend all their salary and resources and, when funds become scarce, resort to swindling, theft, non-payment of debts or drug-peddling. Most coca-paste abusers have psychopathological disturbances before they become addicted to drugs, but some of these young people had been healthy and respected middle-class students, professionals or employees before they began smoking coca paste. It was hard to credit the extremes of social degradation to which people could fall, especially those who had been good students, efficient professional workers or successful business people.
Soon after the first paper on this study was published, Peruvian investigators confirmed the results and added their own observations  ,  . Their description of the natural course of coca-paste dependence was based on information obtained from patients in psychiatric hospitals. Their clinical and sociological observations tallied very closely with those summarized above and confirmed that most patients would develop an intense dependence after six months of coca-paste smoking, characterized by psychological paranoia, stupor and cerebral disorders  .
Another author  was particularly interested in the jargon used by coca-paste smokers and described the natural history of dependence, based on Colloquial descriptions by smokers and observations made on 24 hospital patients [1l] .
Two researchers working in Bolivia  found that coca-paste smoking accelerated the thinking process and led to obsessiveness and a marked compulsion to use the drug; they reported that they almost immediately began to have paranoid thoughts, which were accompanied by intense anxiety. In 35 per cent of the cases, senso-perceptive disturbances were documented. They also found that 80 per cent of the patients resorted on impulse to criminal acts such as theft or fraud to enable them to buy the drug. Coca-paste smoking was highly addictive, producing a psychological dependence that could lead individuals to delinquency, ill-health and imprisonment. Recently coca-paste (bazuco) Smoking has been reported in many parts of Colombia. In 1982, more than 1,200 cases were reported to the Ministry of Health  .
The social repercussions of coca-paste smoking are not limited to family and neighbours. Coca paste has become the main illicit drug exported by drug traffickers from Peru [16- 18]. The enormous profits derived from this huge-scale illegal business give traffickers an extraordinary means of setting up legitimate businesses as "cover" and a considerable capacity for corruption and for maintaining rapid communication, as well as for procuring sophisticated equipment for hiding the drug.
Coca-paste smuggling can have a demoralizing effect on certain sectors of society. Cases have been repeatedly brought to courts of law in which judges, lawyers, congressmen, physicians, politicians, police officers and civil servants had accepted bribes or had become members of an illegal international drug-trafficking organization  . Similar events have been reported in Argentina  , Bolivia  , Colombia [12, 22] and Ecuador  . The loss in manpower and efficiency from illness, addiction, delinquency, imprisonment, absenteeism and Sloppy work habits has been considerable.
In order to verify the effects of coca-paste smoking, the author undertook in 1978 a study of a group of eight healthy middle-class Peruvian males, between 20 and 25 years of age, who smoked Coca-paste. All were volunteers, and none reported any previous organic, mental or nervous disorder. They took part in a smoking session at which they were under observation and stopped when they had had enough. Some showed anxiety or changes in mood. Others became withdrawn and between cigarettes would come out of their isolation only to complain of their depressed mood. A few subjects became garrulous, active and playful when they were smoking, but between cigarettes showed some hostility and moody ambivalence. The latter smoked very quickly to begin with and then voiced a desire to stop but were unable to do so, experiencing extreme dysphoria at the end of the session.
While smoking, all the subjects showed an increased pulse rate, blood pressure and respiration. In some cases the body temperature rose. All of the subjects had dilated pupils, many became shaky and showed increased muscle tone with profuse perspiration. All of them expressed a strong desire for alcohol, which they claimed was necessary to calm them down.
Blood was taken from the veins of the forearm at 15-minute intervals during the smoking session. Two tests were carried out, using liquid gas chromatography and a nitrogen-sensitive detector. At all the sessions, a rapid rise was verified in the plasma concentration of cocaine, to levels of 500 -975 ng/ml, measured within five minutes of smoking 0.5 g of coca paste. It was also found that the subjects became dysphoric when the concentration of cocaine in the blood was still high  .
Even though the amount of coca paste used by the subjects of this study was very small compared with the quantities smoked under illegal conditions by heavy smokers, the following two findings were documented:
Coca-paste smoking produced physiological and psychological changes, including euphoria, dysphoria and paranoid behaviour;
Coca-paste smoking gave rise to rapid and elevated levels of cocaine in the blood, similar to those found after intravenous injection.
As it was difficult to administer psychological tests while repeatedly taking blood from the volunteers for this study, another series of examinations was performed in 1982 without blood Samples  , the main purpose of this being to measure the psychological changes in individuals while they were under the influence of coca paste. Six healthy male volunteers, aged from 19 to 35 years, were examined after they had signed informed consent forms. They were examined by physicians so as to provide a complete medical record, and the following tests were administered: the brief psychiatric rating scale (BPRS); the Addiction Research Center inventory (ARCI); the Wechsler adult intelligence scale (WAIS); the modified profile of mood States (EDES); the World Health Organization?s basic form of drug evaluation (BFDE); and a coca-paste smoking questionnaire (CPSQ). Throughout the sessions, the subjects were repeatedly interviewed individually, applying the BPRS; after each cigarette had been smoked, ARCI, EDES and revised high scale (RHS) tests were completed.
The subjects were placed in two rooms. In one room they were examined every two minutes by a psychiatrist who marked up the linear and behavioural scales. The psychiatrist did not know what substance was being smoked. In the other room, two physicians performed periodical medical examinations, distributed the cigarettes (tobacco only or coca paste with tobacco) and observed the physical changes. None of the subjects knew whether the cigarettes were tobacco only or paste with tobacco. The physiological changes noted in previous research  were verified in all subjects. The BPRS test showed considerable sensitivity to placebo smoking. The ARCI and EDES scores rose with coca-paste smoking. EDES and the RHS tests showed significant swings between euphoria and dysphoria during the different phases of the smoking sessions.
In general, individuals smoking coca paste reported intense mental changes on the linear and behaviour scales, but each one showed different qualitative and quantitative curves. Euphoria associated with anxiety was confirmed in all subjects when they were "high". Dysphoria and other mood changes were documented in later phases. These changes were much more evident in the group of coca-paste smokers than in the group using a placebo  .
Again it must be noted that the amounts of coca paste smoked in this study were relatively small compared with the usual consumption at recreational or heavy sessions. Every precaution was taken to avoid any possibility of severe or psychotic reactions in the subjects who volunteered for the study.
Two years after coca-paste smoking had first been mentioned in the literature on the subject  , this form of drug abuse was reported to be on the increase in Lima  . In the same year, several hundred cases associated with severe psychological disturbances were documented  ,  ,  . One author reported a large annual increase in the number of excessive users of coca paste admitted to a psychiatric hospital  . Several researchers observed the same trend in general and psychiatric hospitals  ,  ,  ,  ,  . These findings corroborated the data on drug seizures reported by the police. Coca paste was the main drug involved and the amounts seized increased every year  ,  . The number of persons apprehended while smoking coca paste in the streets also increased regularly from year to year  ,  ,  . The results of these studies indicated that this form of drug abuse by the general population needed further research.
A special questionnaire was prepared, based on previous work done in New York  and Mexico  . In 1979, a survey was carried out of 2,167 households in the 45 districts of the city of Lima  (see table 1). The survey covered nearly 3 million inhabitants in the 12 -45-year age group. In the course of household interviews, questions were asked about the use of 12 drugs. The survey showed that all the drugs being investigated were abused in Lima by individuals of both sexes. Coca leaf was chewed by 5.4 per cent of the population surveyed, coca paste was smoked by 1.3 per cent and cocaine hydrochloride was used by 0.7 per cent. On the basis of this survey, it was estimated that in 1979 there were 162,000 coca chewers, 39,000 cocapaste smokers and 21,000 cocaine sniffers. In other words 222,000 people in Lima used coca, coca paste and cocaine. Earlier studies  had found that at least 13 per cent of the people in Peru chewed coca leaves, the percentage being much higher in the mountain towns, where children, adults and the aged consumed coca [30 - 32]. If that percentage had been applied to the population of Peru and the data calculated for the population of the Andes, the estimates for 1979 could have been 3 million coca chewers; 156,000 coca paste smokers and 84,000 users of cocaine hydrochloride.
Projections of drug abuse in Lima based on a househoId survey of the population of Lima aged 12-45 years, 1979
The illicit traffic in coca paste and cocaine originates mainly in Bolivia, Colombia, Ecuador and Peru and is destined for the western hemisphere. There has been a considerable increase in the number of abusers of coca paste and cocaine  and the increased demand has stimulated production. In many parts of Bolivia, Colombia and Peru, the coca plant has displaced the fruits, grains, tea, cacao and coffee that used to be cultivated [9,18, 21]. The large production, coupled with a strengthening of repressive measures, has created a local surplus that has been used for domestic consumption and, of course, an excess of cocaine in any nation tends to lead to increased use [9, 16 - 18, 21, 22, 34]. The trend in Peru is clearly shown in table 2 below.
Quantities of cocaine hydrochloride and coca paste seized by the Peruvian Police force, 1972-1981
|Year||Cocaine hydrochloride||Coca paste|
In the past, coca paste was exported to other countries for the production of cocaine hydrochloride. Now it is both exported and sold on the illicit market by thousands of peddlers in cities, towns and rural areas in the producing countries, and it is smoked by people of all ages, in the middle and lower social classes  ,  . Wealthy abusers prefer cocaine hydrochloride.
The effects of coca chewing is dose-related and is manifested by a slight dilation of the pupils, a moderate increase in respiration, an increase in blood pressure and an accelerated heart-beat. Spinal and autonomic reflexes are stimulated and cutaneous sensibility diminishes. Thirst, hunger and fatigue are suppressed. If chewing is excessive, acute toxic manifestations are observed, such as illusions, delusions and hallucinations. If coca leaves are chewed by children for a long time it affects their learning ability  ,  ,  . Although the coca leaf contains a number of alkaloids and other chemical substances, it has been demonstrated that the physical and mental changes produced by its use are mainly due to the presence of cocaine in the blood  ,  .
Coca-paste smoking produces much more marked physical and psychological changes than coca chewing. Even one cigarette will produce definite changes, which are associated with the considerable amounts of cocaine that appear in the blood  ,[ 40] .
Cocaine hydrochloride can be eaten, sniffed, applied to the mucous membranes (ear, nose, eye, vagina, urethra) or injected subcutaneously, intramuscularly or intravenously  -  . In small doses it stimulates nervous and mental activities. In large doses it produces marked physiological changes and unpleasant psychological disturbances, including insomnia, suspiciousness, abnormal ideas, hallucinations and paranoid psychosis. These manifestations are also seen in heavy or compulsive coca-paste smokers  ,[ 8] .
Acute cocaine intoxication is characterized by a rapid progression of anxiety, generalized convulsions, and in some cases arrest of respiration, followed in a few minutes by death  . Recently these reactions were seen in three patients who died while being transported to hospital after having smoked coca paste for several days. They had been coca-paste abusers for several years.
It is well known that humans can develop a tolerance to cocaine. Because of the ready availability of cocaine in Peru, the drug can be consumed in very large amounts, and much larger quantities of cocaine are consumed by abusers in Peru than, for example, in the United States of America  -[ 46] . One patient inhaled up to 15 g of cocaine every day and suffered three prolonged periods of psychotic breakdown  . The patients examined in this study smoked coca paste several times a week, at an average of 3 g a session. Heavy coca-paste users smoke 40 - 60 g a session[ 2] ,[ 3] ,  ,  . One heavy user said that he had smoked 300 g in four days  . Smokers have been observed preparing a "joint" with about 300 mg of coca paste  ,  . The effects produced by smoking these cigarettes were very marked.
In the author?s study of volunteers, "joints" were prepared with 100 mg of coca paste, with only minor effects  . Coca-paste smoking induces physical and psychologic al changes with similar rapidity as intravenous injection of cocaine hydrochloride  , .
Cocaine has been found in the blood of coca chewers, coca-paste smokers and users of cocaine hydrochloride  ,  ,  ,  ,  ,  . These three forms of drug-taking produce dose-related effects, which also depend on other chemical substances taken concurrently, the method of drug-taking and individual reactions. With small doses, the stimulating effects predominate, with larger doses the unpleasant effects take over.
In many individuals, abuse of coca paste and cocaine hydrochloride engenders severe psychological dependence. Psychological changes depend on the amount of cocaine taken  ,  . With high doses, the body is much less efficient in clearing cocaine from the body  . In Peru, heavy abusers of cocaine take well over 3 mg for every kg of body weight, which probably reduces the ability of the body to eliminate the cocaine. This explains why intestinal absorption by smugglers who have swallowed plastic bags filled with cocaine causes death.
In the author?s view, coca-paste smoking began in Peru mainly as a result of peer pressure. In 1966, Peruvian adolescents began using certain drugs that were fashionable at the time  . Young foreign visitors, realizing that coca paste was relatively inexpensive and rich in cocaine, began experimenting with it. The habit spread rapidly throughout the country, and sales of the drug mainly by small merchants grew accordingly. The ready availability of coca paste, as well as suitable conditions and a favourable attitude on the part of certain population groups, were conducive to the spread of the coca-paste epidemic in Latin American countries.
Statistics show that there has been a considerable increase in the production of illegal coca paste and cocaine in Peru since 1970. Similar developments took place in Bolivia  and later in Colombia  and Ecuador  .
In the beginning, high-school pupils were the main abusers of coca paste. The habit soon extended to other groups, first university students, young workers and professionals and, later, middle-aged men and women. In some areas of the country, coca paste was used as a form of payment for agricultural work  ,  .
Certain personal factors, such as rebelliousness, the use of tobacco, cannabis or alcohol, absenteeism, behavioural or learning difficulties at school, psychological disturbances, and neurological or personality disorers, ders, were found to be associated with the development of a dependence on coca paste. A small number of abusers were, however, healthy young people before they started to smoke coca paste.
Social factors, particularly peer-group pressure, contributed considerably to the prevalence of coca-paste smoking  ,  ,  ,  . It was also observed that broken homes, unemployment, crime and a slum environment were important contributory factors.
It seems very difficult to eradicate the coca plantations, which grow larger every year. The growers can earn more money from coca than they can get from other crops. On the other hand, the illicit demand for cocaine is also rising steadily throughout the world. Illegal transactions relating to cocaine involve billions of United States dollars every year and are leading to corruption and crime in many countries. Some terrorist groups supplied with modern weapons are involved in the business in that they protect the cocaine traffickers, who pay them for their services  ,  .
Once a person is addicted to coca-paste smoking, the craving for the drug is so strong that cure and rehabilitation are difficult. It is thought that some "recreational" users, who are acceptably integrated into their communities, do not need treatment. The patients being treated in general and psychiatric hospitals for coca-paste smoking are usually chronic, resistant and relapsing addicts. Treatment results for this group are usually poor. Relapses occur with conventional medico-psychological treatment in about 50 per cent of the cases  -  .
The smoking of free-base cocaine or coca paste can be treated by detoxification, support therapy, self-control strategies, exercise therapies and maintenance of abstinence programmes. As drug addicts may relapse after years of abstinence, follow-up and guidance should be provided for at least five years  ,  ,  ,  .
According to the experience of the author, in order to develop an appropriate therapeutic programme for an addicted individual it is important to assess the pathology that existed before coca-paste dependence was created and, also, to assess the physical, psychological, familial and community factors related to such pathology  ,  ,[ 7] ,  .
The patients with the best prognosis are those who had shown an acceptable adjustment at school or at work and who lived in an integrated family that was able to support its members. Easy access to money and a permissive home environment are conducive to a relapse. When the cocapaste addict returns to a home or community in which drugs are abused frequently, he tends to relapse in a very short time.
The patients who were assessed for this study were treated in several institutions by supportive psychotherapy, work therapy, physical exercise and tranquillizers. Some were treated with intensive psychotherapy by private practitioners, but without any long-lasting effects.
It was very difficult to follow up patients who had been discharged from general, psychiatric and private hospitals because many of them gave incorrect addresses or could not be found at home. The patients who could be traced were frequently seen to have suffered a relapse, to have been involved in accidents, to have suffered from physical disease or to have attempted suicide. Some of them had died as a result of homicidal attacks. Of 348 patients discharged from hospitals, 156 (44.8 per cent) were followed up in one year and 61 of them were found to be drug-free.
Coca-paste smoking is a severe disorder, with grave consequences for the individual, the family and the community  ,  . More effective measures are urgently needed in the countries in which it is prevalent. Such measures should be carried out by Governments, with help from international organizations and the industrialized countries.
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