History of Drug Exposure as a Determinant of Drug Self-Administration

The purpose of this paper is to review how a drug’s effectiveness in initiating and maintaining self-administration can be influenced by a subject’s past experience with drugs. Drug self-administration by humans and laboratory animals is considered an instance of operant behavior (), controlled by the subject’s genetic constitution, past history, and the current circumstances of drug availability (of Skinner, 1938). The influence of history of drug exposure on current drug-maintained behavior may be controlled, in turn, by the particular drugs and doses employed and the conditions under which the drug is administered. This discussion will focus on the ways in which a history of drug exposure can control later drug self-administration in laboratory animals. Effects of history of drug exposure on initiation of drug self-administration In order to study drug self-administration by laboratory animals, an experimenter must set up a situation in which subjects are exposed to some contingency between the occurrence of a specific response and delivery of a particular drug. For many drugs, no explicit behavioral or pharmacologioal history is necessary for the drug to maintain behavior. In one initial study, for example, Read more […]

Behavioral Pharmacology of Narcotic Antagonists

Narcotic antagonists are currently the major pharmacological alternative to methadone for the long-term treatment of narcotic addiction. The clinical utility of antagonist treatment is undergoing continuing evaluation (). Within the last five years, there have been several comprehensive reviews of research on narcotic antagonist drugs (). This review will focus upon some recent behavioral studies of narcotic antagonist drugs in man and in animals. It is now apparent that antagonist drugs may have a number of complex behavioral effects, in addition to antagonism of the pharmacological effects of opiate drugs (). Recent explorations of the aversive properties of some antagonists () have been complemented by studies of the positive reinforcing qualities of antagonist drugs. The finding that opiate dependent monkeys will work to produce an infusion of a narcotic antagonist under certain conditions () suggests the complexity of the process of drug-related reinforcement (). Narcotic agonists and antagonists each may maintain behavior that leads to their administration. Of the several compounds which have narcotic antagonist properties), only two appear to be relatively “pure” antagonists with minimal agonistic activity. Read more […]

Outpatient Treatment and Outcome of Prescription Drug Abuse

Forty-six consecutive patients who voluntarily sought outpatient treatment for abuse of one or more prescription drugs were studied. Barbiturates, amphetamines, and diazepam were the most common drugs abused. Desired treatments by patients included counseling, medical withdrawal, or medical maintenance with the drug of abuse or a chemically related drug. Twenty-two (47.8 percent) patients left treatment and relapsed within one month; another eight (17.4 percent) patients relapsed between one and three months after entering treatment. Only 13 (28.3 percent) reported abstinence 90 days after entering treatment. This experience suggests that a wide range of medical, social, and psychologic resources are required to treat prescription drug abuse, and that long-term drug abstinence is difficult to achieve with all patients. Treatment of prescription drug abuse has dealt primarily with drug complications such as overdose, toxic reactions, and techniques for medical withdrawal. Other reports describe behavior patterns of prescription drug abuse and often refer to it as poly-drug abuse, since many persons frequently abuse more than one drug. Some reports emphasize the clinical complexity of poly-drug abuse and particularly Read more […]