Chapter 2 Drug-Taking Behavior: Personal and Social Concerns

Drug Toxicity A drug’s harmful effects are referred to as its toxicity. Acute toxicity can be computed from its effective dose response and lethal dose-response curves. Two commonly used measures are the therapeutic index and the margin of safety.

Figure 2.1 therapeutic index: LD50/ED50 margin of safety: LD1/ED99 for what effect?

An effective dose (ED) of a drug depends upon __________. A. the drug effect under consideration B. the percentage of the test population you have specified C. both A and B D. neither A nor B

Figure 2.2

The DAWN* Reports In general, DAWN statistics show that cocaine and narcotic drugs are both highly toxic and that many emergencies involve drugs being taken in combination with alcohol. There are also recent concerns about the increasing number of emergencies associated with club drugs and opiate-based pain relief medications. What are the problems associated with using DAWN reports to estimate the abuse of drugs? *Drug Awareness Warning Network

From Acute Toxicity to Chronic Toxicity The number of people who die each year as a result of drinking alcohol or smoking tobacco far outstrips the number of fatalities from the abuse of illicit drugs. What is the difference between acute and chronic toxicity? Alcohol as an example?

© Copyright 2011, Pearson Education, Inc. All rights reserved. In terms of toxicity, a drug with a therapeutic index of two ______ a drug with a therapeutic index of ten. A. is roughly equivalent to B. is safer than C. is more dangerous than D. cannot be compared to

Figure 2.3

Behavioral Tolerance and Drug Overdose A tolerance effect is the capacity of a drug to have a gradually diminished effect over repeated administrations; in effect, a greater dose has to be taken to maintain the original effect of the drug. Tolerance effects can be quite dangerous, because experienced drug users often end up taking potentially lethal dose levels.

Behavioral Tolerance and Drug Overdose The setting within which drug-taking behavior occurs is an important factor in behavioral tolerance. Behavioral tolerance effects are based on the principles of Pavlovian conditioning.

Naive Tolerant Tolerance is evidenced by a shift in the dose-response curve to the right Higher dose needed to achieve the same effect. The same dose produces a lesser effect. How is tolerance reflected in a dose-response curve?

Physical and Psychological Dependence Drugs can be viewed in terms of a physical dependence model, in which the compulsive drug-taking behavior is tied to an avoidance of withdrawal symptoms, or a psychological dependence model, in which the drug-taking behavior is tied to a genuine craving for the drug and its highly reinforcing effects on the user’s body and mind.

Physical and Psychological Dependence Physical dependence: need for a drug to restore normal brain function because of primary changes in the brain induced by the drug (e.g. tolerance). Psychological dependence: need for a drug due to secondary changes in the brain and experiential (i.e. conditioned) effects. Unlike physiological dependence, psychological dependence may generalize between drugs having very different pharmacological modes of action. There is large overlap between the concepts of physical dependence and psychological dependence.

Figure 2.4

Psychiatric Definitions The American Psychiatric Association currently recognizes two major conditions associated with drug-taking behavior: substance dependence and substance abuse.

Table 2.1

Psychiatric Definitions The broader term “substance” is used instead of “drug,” because there is often confusion in the public mind about what is defined as a drug and what is not.

Special Circumstances in Drug Abuse Increasing attention has been directed toward the harmful effects that drug abuse has on pregnant women, in terms of problems both with the pregnancy itself and with the neural development of the fetus. There is also concern about the increased risk of HIV infection (and the spread of AIDS) among intravenous drug users when needles are shared.

According to the text, what are the effects of using cocaine or crack during pregnancy? A. constriction of blood vessels, reducing normal blood flow to the fetus B. high rates of spontaneous abortion C. growth retardation such as lower birth rate and smaller head circumference D. all of the above

Drugs, Violence, and Crime There is an overall association between the taking of illicit drugs and crime, but careful analysis indicates that the drug with the closest connection to social violence is alcohol, and that heroin and marijuana cause the user to be less inclined toward violent behavior rather than more so. Modern synthetic drugs of abuse, such “spice” and “bath salts” are unregulated and of unknown composition. Physiological and behavioral effects are consequently unpredictable.

Drugs, Violence, and Crime It is clear that drug abuse prompts many drug users to commit criminal acts (most commonly property theft and prostitution) to support the drug habit. It is also clear that there is a high level of social violence and criminal behavior inherent in the trafficking and distribution of illicit drugs.

Figure 2.5

Which criterion is not used for a DSM-IV-TR diagnosis of substance dependence? A. tolerance B. withdrawal symptoms C. persistent desire or efforts to control drug use D. increased willingness to try new drugs

© Copyright 2011, Pearson Education, Inc. All rights reserved. According to the text, a majority of homicides and sexually aggressive acts are committed by users of __________. A. crack cocaine B. heroin C. alcohol D. nicotine

Governmental Policy, Regulation, and Laws Since the beginning of the twentieth century, U.S. society’s philosophy toward drug-taking behavior has been that we should restrict it by reducing the availability of illicit drugs and making it as difficult as possible for the potential drug user to engage in drugtaking behavior.

Governmental Policy, Regulation, and Laws The Harrison Act of 1914 was the first of several legislative efforts to impose criminal penalties for the use of opiates and cocaine and of later marijuana, hallucinogens, and several other types of drugs. The Comprehensive Drug Act of 1970 organized the federal control of drugs under five classifications called schedules.

Table 2.2

Governmental Policy, Regulation, and Laws Overall planning and implementation of drug policy in the United States now originate from the White House Office of Drug Control Policy.

Enforcement of Drug Laws on a Global Scale Today’s drug-law-enforcement program in the United States places considerable emphasis on the interdiction of drugs entering the country and less emphasis on the treatment and prevention of drug abuse.

Figure 2.6

Enforcement of Drug Laws on a Global Scale Attempts to reduce the influx of illicit drugs into the United States are complicated by a series of economic and political factors on a global scale, particularly with respect to international relations with nations such as Colombia, Mexico, and Afghanistan that have been involved either in drug cultivation or in trafficking.

Enforcement of Drug Laws on a Global Scale The intertwining and sometimes opposing goals of America’s drug-control policy and global foreign policy continue to be a major challenge. What approaches might be more effective in controlling drug abuse in this country? What aspects of the drug abuse problem would they control? illegal activities violence addiction other mental/physical health problems