Advances in alcohol & substance abuse最新文献

The benzodiazepines were first introduced in 1960. Chlordiazepoxide (Librium) was the first of the class of drugs called benzodiazepines, in a deliberate attempt to synthesize a tranquilizer without the sedative properties and abuse, addiction, tolerance, and dependence potential of the barbiturates, and other sedative/hypnotic drugs. The popularity of the benzodiazepines rose steadily to a peak period in the mid 1970s when diazepam (Valium) was the most commonly prescribed drug of any kind, including antihypertensive, analgesic and other psychotropic medications. The current evaluations of benzodiazepines use and abuse demonstrate clearly that they produce tolerance and dependence in short and long-term administration. The development of abuse and addiction is also strongly substantiated although they are not as easily appreciated and identified because of confusion in diagnosis and treatment of abuse and addiction. Significant problems in definitions, diagnosis, interpretations and conclusions exist in general practice regarding abuse and addiction, and their relationship to use of and symptoms produced by benzodiazepines. The lack of clarity in defining abuse and addiction and tolerance and dependence in clinical practice leads to institution and perpetuation of the toxicity and untoward effects of the benzodiazepines.

We surveyed 1703 first-year students at the University of Virginia one month after arrival who used alcohol at some time in their lives. Our survey looked at drinking practices and psychosocial patterns. Men drank more and more often than women. Our data suggest that in defining frequent heavy drinkers, one should consider body weight. Now, we define frequent heavy drinking as five or more drinks in a row at least weekly for men, and for women, we use three to four drinks or more in a row at least weekly. Frequent heavy drinkers and students with psychosocial problems appeared disproportionately among students planning to join fraternities and sororities. We believe efforts to correct alcohol abuse and addiction by college students must focus, at least in part, on social organizations, especially fraternities and sororities. Also, we must attend to psychosocial features that predispose to alcohol abuse and addiction.

The study was undertaken to determine whether morbidity and mortality rates for alcoholic cardiomyopathy vary with community alcohol consumption levels. The cardiomyopathy mortality comparisons for Australia from 1968 to 1978 showed a positive relationship for both males and females aged 30 to 59 years, and 60 years and over. From 1979 to 1986 a decrease in consumption was associated with a decrease in alcoholic cardiomyopathy mortality for females, and to a lesser extent males, aged 30 to 59 years. The morbidity comparisons for Western Australia from 1971 to 1984 gave similar results to the Australian mortality findings for the males aged 30 to 59 years. It appears that the prevention of alcoholic cardiomyopathy will be facilitated by lowering the overall level of alcohol consumption in the community.

This chapter examines positive and negative reinforcement mechanisms which play a significant role in alcohol abuse and alcoholism. Consideration is given to the role of euphoria and anxiolytic effects of alcohol as the basis of positive reinforcement, and physical dependence and aversive consequence of drinking as the basis of negative reinforcement. The motivational significance of each of these is discussed with respect to various animal models of addiction and clinical and human research. Brain neurochemistry, neuropharmacology and genetic research data are evaluated from the perspective of reinforcement mechanisms involved with alcohol addiction.

This article reviews the literature on relationships between patient characteristics and outcome of inpatient treatment for alcoholism. The article is organized according to categories of patient variables which have been studied. These include psychological characteristics, demographic variables, degree of alcohol dependence, motivation for treatment, coping styles, and beliefs about abstinence from alcohol. Conclusions based on the studies reviewed are presented, along with a discussion of why definitive conclusions are rare in the field of alcoholism treatment research. Conceptual and methodological issues in this research area are highlighted in attempting to come to some coherent and integrated conclusions regarding the current state of knowledge, and directions for current and future research are discussed.

In this review phencyclidine and related arylcyclohexylamines and hallucinogens, using LSD as the prototype, are considered as two distinct classes of abused drugs. Within these classes drugs that are found on the street are discussed, and a current epidemiological summary is provided. The abuse liability and dependence potential of these drugs are evaluated by considering four major determinants of their abuse. First, is the ability of a drug to function as a positive reinforcer and increase the probability of operant behavior leading to its delivery. Animal data describing the reinforcing effects of PCP are reviewed with respect to the influence of variables controlling drug-reinforced behavior; however, there are no animal models of hallucinogen-reinforced behavior. Several methods of quantifying reinforcing efficacy are discussed. A second determinant is the subjective effects of the respective drugs. These effects are described and compared across drugs based on clinical reports in humans and drug discrimination studies in animals. A third determinant is the behavioral and physiological toxicity that results from acute and chronic use of these drugs. Clinical reports and results of sensitive tests that have been developed for laboratory animals are reviewed. A fourth determinant is the dependence potential that exists with these drugs, measured by tolerance development and the extent to which behavioral and physiological disturbances occur when drug use is terminated.

The principal action of the sedative-hypnotic drugs, of whom the barbiturates are the most widely known and utilized, is to produce drowsiness and promote sleep. At one time these were also the only drugs available to calm seriously anxious or disturbed people. Unfortunately, in addition to their clinical applications these drugs manifest a very high abuse potential. Experienced drug abusers report feelings of well-being and euphoria while under the influence of these drugs. Self-administration experiments conducted in animals have shown that the barbiturates are potent reinforcing agents. In controlled studies in humans, former drug abusers express a preference for barbiturates over benzodiazepines and will "work" to receive barbiturates. Long term consumption of the sedative-hypnotics, particularly barbiturates, leads to dependence characterized by a severe, potentially life-threatening abstinence syndrome following the abrupt withdrawal of the drug. Withdrawal manifestations include delirium and grand mal seizures. Because of the high abuse potential of these drugs, their manufacture and distribution has been greatly curtailed, and for most clinical applications they have been largely replaced by drugs, e.g., the benzodiazepines, which appear to have much less abuse liability.

The erythrocyte membranes from 9 healthy non-alcoholic controls and 8 alcoholic patients (fulfilled DSM-III-R criteria for alcohol dependence) were compared for changes in membrane order as measured by fluorescence polarization. The mean amount of change in fluorescence polarization in response to in vitro exposure to ethanol was significantly less in the alcoholics than controls. This increased membrane order of the peripheral blood erythrocytes suggests the presence of pharmacodynamic tolerance to ethanol in the alcoholic patients.

A review of scientific and clinical evidence indicates: (1) benzodiazepines have an abuse liability and can cause physical dependence, (2) abuse liability is of a lower order of magnitude than that associated with common intoxicants such as barbiturates, opioids or stimulants, (3) sustained, exclusive use of benzodiazepines for inducing intoxication occurs but, it is infrequent, (4) benzodiazepines tend to be secondary drugs to a preferred primary intoxicant; in experimental paradigms normals prefer placebo to benzodiazepines, (5) susceptibility to physical dependence varies widely as low doses are sufficient to produce it in some but very high multiples are not sufficient to produce it in many others, (6) factors predisposing to physical dependence are: total lifetime dose, previous exposure to drugs cross-tolerant, such as alcohol or barbiturates, concomitant severe medical/psychiatric problems, and severe persisting stress. Individual susceptibility to abuse and to become dependent on benzodiazepines should be investigated much more vigorously than it has heretofore.