Cocaine: Longitudinal study of users (1975-1983)



A total of 118 cocaine users were recruited for study in 1974. Of these, 19 were selected for interview and questionnaire study while 99 (85 males, 14 females) were selected for a more comprehensive longitudinal study. All 99 users (18-38 years old) were social-recreational users who met the initial requirement of having used a minimum of 1 gram of cocaine per month for 12 months (range 1-4 grams). The majority of users were students (73 percent,) while others listed their occupations as housewives, business people, writers, attorneys, physicians, secretaries, teachers, or unemployed. Exaninations and tests were performed on each subject at 6-month intervals for 4 years (1975, 1976, 1977, 1978) and then at approximately 18-month intervals for another 5 years. Examination procedures included a personal history questionnaire, drug history questionnaire, subjective drug effects questionnaire, mental status exanination, the Minnesota Multiphasic Personality Inventory (MMPI), the Experiential World Inventory (EWI), in-depth interviews, and physical examinations (for most subjects). In addition, assays were performed on samples of cocaine used by these subjects. An important caveat is that a number of users dropped out of the study throughout the years or could not be located for followup examinations. Several followup examinations in the last 5 years of the study were conducted via telephone, and these were restricted to questionnaires and interviews. Nevertheless, a total of 61 users participated in all phases of the first 4 years of study and 50 users were available for followup in 1983. Eight additional users who refused followup examinations reported that they had stopped all cocaine use.

Preparations and Purity

All subjects used cocaine hydrochloride available through illicit markets. The average purity of their samples fluctuated throughout the years of the study: 43.2% in 1975; 56.2% in 1976; 52.1% in 1977; 60.8% in 1978; 25.0% in 1979; 13.9% in 1980; 48.7% in 1981: 58.0% in 1982; and 75.0% in 1983. When cocaine free base was prepared, the average purity of the final product was 95.0%. The most common adulterants and diluents were mannitol, lactose, inositol, lidocaine, and phenylpropanolanine.

Routes of Administration

All subjects employed the intranasal route at the start of the study period. By the end of the first year, 14 percent had experimented with smoking cocaine hydrochloride on tobacco or marijuana cigarettes. By 1978, 39 percent of the users had smoked cocaine as the hydrochloride or free base and 10 percent classifed themselves as primarily cocaine free base smokers. For the last 5 years of study, there were two distinct populations of users: intranasal users (90 percent) and cocaine free base smokers (10 percent). Throughout the study, users experimented with other routes including injection (n=5) and oral (n=ll).

Dosages and Dose Regimes

Intranasal users administered cocaine in amounts (uncorrected for purity) of 20 g per &ministration if a “cokespoon” was employed or 50 g if “lines” were used. Throughout 1975-1978, intranasal users averaged between 1 and 4 grams (uncorrected weight) per month. From 1978 to 1983, intranasal users, approximately 90 percent of the sample, averaged between 1 and 3 grams per week. Cocaine free base smokers, approximately 10 percent of the sample, used approximately 100 mg of free base per “hit” or inhalation. Throughout 1975-1978, smokers averaged 1 gram per day during periods of use. From 1978 to 1983, smokers averaged 1.5 grams per day. The temporal spacing of hits and the total duration of a smoking episode varied considerably . Inhalations were repeated as often as every 5 minutes during binges ranging from 30 minutes to 96 hours. Individual consumption ranged from 1 gram to 30 grams per 24-hour period, although some users reported smoking up to 150 grams in 72 hours. Smoking episodes continued until supplies of cocaine were depleted or users became exhausted and fell asleep.

Patterns of Use

All 99 users were classified initially as social-recreational users, since use generally occurred in social settings among friends or acquaintances who wished to share an experience perceived by them as acceptable and pleasurable. Such use was primarily motivated by social factors and did not tend to escalate to more individually oriented patterns of use. Use tended to occur in weekly or biweekly episodes. From 1975 to 1978, 75 percent (n=46) of the users still in the study (N=61) engaged in episodes of more frequent use (see below) but remained primarily social users. From 1978 to 1983, 50 percent (n=25) of the users still in the study (N=50) remained social-recreational (with continuing episodes of increased use), 32 percent (n=16) of the users became primarily circumstantial-situational users, 8 percent (n=4) became intensified users, and 10 percent (n=5) became compulsive users. Importantly, this latter compulsive group consisted entirely of cocaine free base smokers.

An important caveat is that all users had episodes of decreased use or abstinence interposed between periods of use in their normal patterns. Thus, users reported abstaining from cocaine for periods ranging from a few days to several months. For example, from 1978 to 1983, four social-recreational users reported no use for 2 years. During this same period, all compulsive users reported periods of social use as well as brief periods of abstinence. And most users in all categories reported that supplies of cocaine were often unavailable, thus resulting in regular periods of nonuse. However abstinence also occurred during periods of cocaine availability.

Thus, 25 social-recreational users at the beginning of the study remained in this pattern of use after 9 years. Throughout this period, these users continued to report positive effects of intoxication including euphoria and stimulation, although they also reported negative effects including nasal problems, restlessness, and attentional difficulties. By restrictiting themselves to social patterns of use, they reported the ability to titrate their doses and thereby minimize these negative effects. Reliefs in cocaine as an “ideal safe drug” which facilitated social behavior, the economics of supply, and the legal risks of use all seemed to contribute to maintaining stable patterns of use which did not change substantially for these people. The incompatibility of cocaine use with other activities (e.g., work) also served as controlling determinants.

Circumstantial-situational use was defined as a task-specific, self-limited use which was variably patterned, differing in frequency, intensity, and duration. This use was motivated by a perceived need or desire to achieve a known and anticipated drug effect deemed desirable to cope with a specific condition or situation, Use tended to occur in four or five episodes per week. Sixteen of the social-recreational users adopted this pattern of use by 1983. The major motivations cited by users were to increase energy or performance at work and to enhance mood during periods of boredom or depression.

Four users became classified as intensified cocaine users by 1983. Intensified use is characterized by long-term patterned use at least once a day. Such use was motivated chiefly by a perceived need to achieve relief from a persistent problem or stressful situation or a desire to maintain a certain self-prescribed level of performance. While sane social – recreational users referred to their periods of intensified use as short-term runs or binges, these four users reported that they were on repeated runs of several months’ duration and did not return to social pat terns of use.

Compulsive use is characterized by high frequency and high intensity levels of relatively long duration, producing sane degree of dependence. The dependence is such that the individual user does not discontinue such use without experiencing physiological discanfort or psychological disruption. The five compulsive users found here were all cocaine free base snokers. Use tended to occur in episodes of continuous smoking for periods of several hours to 96 hours. These users were characterized by significantly reduced individual and social functioning. The motivation to continue compulsive levels of use was primarily related to a need to elicit the euphoria and stimulation of cocaine in the wake of increasing tolerance. Compulsive users were also motivated by the desire to avoid the discomfort and depression of withdrawal. Consequently, compulsive users were preoccupied with obtaining adequate and sufficient amounts of cocaine in order to forestall an abstinence-like syndrome. When compulsive users were sufficiently well supplied so that preoccupation with obtaining cocaine did not occur, it was common to find an equally intense preoccupation with using such supplies.

Acute and Chronic Effects

Users reported that a variety of acute intoxication effects were perceived as positive. These included: euphoria, stimulation, reduced fatigue, diminished appetite, garrulousness, sexual stimulation, increased mental ability, and increased sociability. Other acute effects were experienced as negative: restlessness, anxiety, hyperexcitability, irritability, and paranoia. During 1975-1978 all users reported experiencing some positive effects in all intoxications and negative effects in only 3 percent of the intoxications. However, during 1979-1983 all users, except compulsive users, reported positive effects in all intoxications but negative effects in approximately 40 percent of the intoxications. Compulsive users reported the absence of positive effects in 15 percent of the intoxications and negative effects in 82 percent of the intoxications. The acute and chronic effects reported by these compulsive users, all of whan were smoking cocaine free base, did not differ substantially from those seeking clinical attention. These are discussed elsewhere ().

Several positive and negative chronic effects were reported by users. The positive effects included: a generalized feeling of increased energy, increased sensitivity to cocaine, general mood elevation, and weight loss. Negative effects included restlessness or irritability, attentional or perceptual disturbances, nasal problems, and fatigue or lassitude. During 1975-1978, users reported a gradual reduction in the frequency of these chronic positive effects and a concomitant increase in the frequency of chronic negative effects such as fatigue (Siegel 1980, table 2). From 1979 to 1983, there appeared to be no further changes in the relative frequency of positive and negative effects for social-recreational users. Overall, these social users reported some chronic positive effects in all intoxications while negative effects were experienced in 11 percent of the intoxications. Conversely, the ratio of chronic positive to negative effects appeared to decrease with patterns of increased use. Thus, circumstantial users reported percentage ratios of 74 percent (positive effects) to 25 percent (negative effects) and intensified users reported 56 percent (postive effects) to 32 percent (negative effects). Compulsive users reported chronic positve effects in all intoxications and negative effects in 71 percent of the intoxications.

Toxic Crisis Reactions

In addition to the negative effects described above, users reported adverse physical and psychological toxic reactions. Toxic physical reactions were defined as acute crises consisting of at least one of the following symptoms: myoclonic jerking, chest pains, nausea or vomiting, respiration difficulties or failure, seizures or convulsions, or unconsciousness. More commonly experienced physical symptoms such as blurred vision, nasal problems, or insomnia were not classified as crisis reactions. Toxic psychological reactions were defined as acute crises with at least one of the following symptoms: hallucinations with delusions, violent loss of impulse control, or attempted suicide. More commonly experienced psychological symptoms such as psychomotor agitation, depression, paranoia, or situational impotency were not classified as crisis reactions here. During 1975-1978, users reported no toxic physical or psychological crisis react ions. From 1979-1983, the social-recreational users continued to report no toxic physical or psychological crises. Also during 1979-1983, 18 percent of the circumstantial users reported an average of four physical crises and one psychological crisis, all instances of impulse dyscontrol. All intensified users reported an average of two physical crises and one psychological crisis. All compulsive users also reported experiencing adverse crises during this latter period. The incidence of these reactions was so frequent that canpulsive users could not accurately estimate their number. However, they reported that both physical and psychological crises developed in approximately 10 percent of their intoxications. The nature of these toxic crises for compulsive users has been discussed elsewhere ().

Personality Profiles

During 1975-1978, retesting with the MMPI detected no pathological deviations from normal T-score means for adults. However, a slight but insignificant elevation in D scales (Depression) and Pa scales (Paranoia) was noted for 7 percent of the users on at least one retest during this period. Also during this period, the EWI retesting indicated that 38 percent of the users displayed elevated Euphoria scales. This suggests increased happiness and contentment with life. Concomitantly, 5 percent showed increased suspiciousness or paranoia, but this was usually directed at concern over their own bodies (hypochondriacal complaints, perceptual disturbances, rhinit is) rather than paranoid ideation concerning others.

From 1979 to 1983, retesting continued only with the EWI. The social-recreational and circumstantial-situational users showed no significant abnormal scores during this period. Most displayed elevated euphoria scales but these were not significant. The four intensified users did not show abnormal T-scores but all showed elevated scores on scales suggesting concern centering around their bodies, egocentricity, and disturbances in social adjustment and comnunication. The five compulsive users displayed marked elevations in almost all T-scores. The typical configuration of these scores suggested a paranoid profile with features of depression, reduced frustration tolerance, problems of social adjustment and communication, disturbances in sleep-wake rhythms, and difficulties in impulse regulation.

Multiple Drug Use

At the beginning of the study, all subjects had past and current (1975) histories of multiple drug use. Prior to their cocaine use, they reported experience with alcohol (100%), marijuana (100%), amphetamines (27%), barbiturates (20%), hallucinogens (10%), diazepam (10%), methaqualone (2%), and opiates (2%). During 1975-1978, the average percentage of subjects using other drugs were: alcohol-85%; marijuana-66%; amphetanines-8%; hallucinogens-5%; diazepam-4%; opiates-4%; and methaqualone-4%. During 1978-1983, the following distribution was reported: alcohol-70%; methaqalone-30%; marijuana-24%; hallucinogens-18%; diazepam-13%; opiates-10%; and amphetanines-2.5%. An important caveat is that these drugs were not necessarily coadministered with cocaine. Many of these drugs were used to treat the hyperexcitability and stimulation produced during periods of excessive cocaine use.


Since all users were monitored on a regular basis, few sought independent treatment for cocaine-related problems. Nonetheless, a number were given referrals for specific complaints: two users developed perforated septums; two developed skin problems associated with cocaine smoking: and six became involved in legal problems associated with possession of cocaine. Following toxic crisis reactions, two users summoned paramedics and one user want to the emergency room of a local hospital. One intensified and one compulsive user chose to enter a formal clinical treatment program.

Most users initiated self-control strategies in order to treat their own negative effects and crisis reactions. The most common strategy was to titrate or restrict the amount of cocaine used in a given period of time. This was usually accomplished by purchasing or carrying a limited anount of cocaine at a time. Social-recreational users reported success in this method. A few users attempted to control use by combining supplies of cocaine with cocaine substitutes, commercial products containing local anesthetics and stimulants that mimic the effects of cocaine.

Other users initiated strategies whereby they periodically abstained from cocaine in an effort to “detoxify” and/or “recover from cocaine effects” for periods ranging from a few days to a few months. The most common negative effects prompting abstinence were nasal problems and irritability. Three major strategies were employed. In avoidance strategies, users attempted to avoid all contact with cocaine, cocaine paraphernalia, and cocaine users. Some users reported that it was effective simply to avoid dealers or other social users. Others engaged in destruction of paraphernalia, and still others employed physical constraints by taking a vacation. In aversion strategies, users sought out and embraced information and stories containing aversive stimuli. Perhaps the most common stories were those that circulated about individuals suffering toxic reactions. These folklore stories told of frequent incidents of bizarre behavior, economic distress, casualties in the criminaljustice system, and toxic overdoses. The stories appeared to generate much concern and anxiety, prompting at least one intensified user to seek counseling and encouraging many others to return for periodic followup examinations throughout the study. In these exams, users would ask for verification of the folklore as well as explanations for cocaine-related effects. In self-initiated contingency contracting, which differs from clinical models (), users made a public pledge to family or peers and asked for support in maintaining abstinence. This support took the form of denial of cocaine supplies, tight controls over financial resources, and careful monitoring of behavior. Surprisingly, pledges were often made to dealers so that they would no longer supply cocaine, and many users reported such contracts were honored by their dealers. However, since the contracts were initiated and maintained verbally, they were easily broken after periods ranging from 1 week to 6 months.


Considering the escalating toxicity and dependency associated with long-term use of stimulant drugs, the most apparent aspect of these findings is that many of the social-recreational cocaine users do not change their long-term pattern of use and do not appear to develop toxic crisis reactions that may warrant clinical attention. Thus, this population of users differs substantially from those “abusers” who experience physical or psychological dysfunction and seek clinical treatment ().

Fully 50 percent of the social users available for followup in 1983 retained this pattern of use from 1975-1983. One common factor cited for such controlled recreational use is the rate-limiting effect of cocaine’s high financial cost. Fourteen of these users were students in 1975 and, throughout the study period, graduated and entered higher income levels. Yet only three escalated use from the initial social patterns. Two users, who were law students and became attorneys, developed circumstantial-situational patterns: the third, a medical student who became a physician, became a compulsive user. The 12 ex-students who remained social users, as well as the other users in this category, all reported stable patterns of cocaine use independent of increased income available for the drug. Thus, the notion that cocaine use is exclusively limited by cost is not supported in this group.

Surprisingly, social-recreational users maintained relatively stable patterns of use when supplies were available and when they were not purposely abstaining. These users ranked cocaine as their recreational drug of choice. It was viewed by users as a social drug which facilitated social behavior. When restricted to social situations, users reported that cocaine was “ideal” in terms of convenience of use, minimal bulk, rapid onset of effects, minimal duration of action with few side effects, a high degree of safety, and minimal after effects. Users reported that this set and setting were the major factors controlling the pattern of use. In addition, they reported that the inconsistent quality of street cocaine, together with a rapidly developing tolerance to the euphoric effects, contributed to controlled use. Legal risks, supply, and cost were cited as minor factors.

The intranasal cocaine users averaged between 1 and 4 grams per month during 1975 to 1978. From 1979 to 1983, these users increased use to an average between 1 and 3 grams per week. The hypothesis that increased dosayes result in increased risks of negative effects and toxicity is partially supported by findings here. Social-recreational users averaged 1 gram per week during 1979-1983 and manifested significant increases in acute and chronic negative effects despite the absence of crisis reactions. Circumstantial-situational users averaged 2 grams per week during 1979-1983 and displayed increased chronic negative effects in 25 percent of the intoxications as well as Some crisis reactions. Three of these users reported an average of four physical crises and one psychological crisis. Intensified users averaged 3 grams per week during the some period and reported chronic negative effects in 32 percent of the intoxications along with an average of two physical and one psychological crises. The relative reduction of crises in the intensified users may be partially related to behavioral tolerance that could be associated with daily patterns of use. Tolerance may also explain the reduction in positive effects reported by both circumstantial-situational and intensified users. However, such tolerance seems to have been easily overshadowed by the escalating dosages of compulsive use. Indeed, compulsive users, all of whom smoked cocaine free base, reported experiencing chronic positive effects in all intoxications, negative effects in 71 percent of the intoxications, and crises in 10 percent of the intoxications. Compulsive users also manifested profiles of a paranoid disorder, while most other users only displayed profiles of heightened euphoria.

The hypothesis that long-term use of cocaine is inevitably associated with an escalating dependency marked by more frequent patterns of use is not supported by these findings. While little is known about the 41 users who dropped out of the study at sane time during the 9 years, 8 social-recreational users who refused to report for followup examinations after 1979 explained that they had stopped all use of cocaine. During 1979-1983, several users reported abstaining for periods ranging from a few days to several months. Four social-recreational users stopped all use for 2 years in the middle of the study. Even compulsive users reported periods of social use or brief periods of abstinence. Thus, users periodically attempted to treat themselves with strategies of controlled use, forced abstinence, or even multiple drug use.


Selections from the book: “Cocaine: Pharmacology, Effects, and Treatment of Abuse”. John Grabowski, Ph.D., ed. Content ranges from an introductory overview through neuropharmacology, pharmacology, animal and human behavioral pharmacology, patterns of use in the natural environment of cocaine users, treatment, through commentary on societal perceptions of use. National Institute on Drug Abuse Research Monograph 50, 1984.