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GETTING CAUGHT

24 Temmuz

GETTING CAUGHT

Most people believe that they will not get caught. Teenagers, in particular, have the feeling that they are "beyond the law" But it does happen. It hap­pens to grandmothers, teenagers, lawyers, doctors, and the most ordinary people on the face of the earth.
Many drug arrests come from the most random events imaginable. In Virginia, an officer stopped a car for having something hanging off the rearview mirror. He became suspicious, legally searched the car, and found major quantities of cocaine. Another drug transporter thought he had the perfect scheme and filled fruit juice cans with cocaine, then resealed them. It is a regular practice for tourists to bring back food from vacation in the Caribbean, and he expected to walk right through customs. What he did not realize was that customs officials knew there was no reason to bring
canned fruit juice from the Caribbean, where it is expensive, to the United States, where it is cheap. He was arrested and convicted for transporting millions of dollars' worth of cocaine.
Even grandmothers are not immune to arrest. A pair of DEA agents working a bus station in North Carolina noticed an elderly woman behav­ing oddly. When they approached her, she moved away and they became suspicious. They conducted a legal search and found a large quantity of cocaine in her luggage.
A college student came back to her dorm room to find the place crawl­ing with campus and city police. While she had absolutely no role in any illegal activity, a friend of her roommate had come to town from another college with a shipment of drugs. Another student, obeying the honor code, had called the campus police. Fortunately, the innocent student was not arrested because the roommate cleared her, but it was a very close call.
The law-enforcement community is actually quite sophisticated in its drug-enforcement efforts. DEA agents work all over the world trying to prevent the transport of drugs into the United States. They have agents working major and minor airports, and even bus stations. The highway patrols of most states have drug interdiction units looking for suspi­cious vehicles. This is not a trivial effort, and it results in so many con­victions that both the state and federal prison populations have grown dramatically.
Yet everyone realizes that most countries are overrun with drugs. It is usually easy to buy the most common illegal drugs in many areas of cit­ies and on college campuses. So why is the legal interdiction effort per­ceived as failing? It is not exactly failing, but rather it is being overwhelmed. Many, many people are caught in the legal system, but there is always someone else to replace each person caught. Routine usage of cocaine, crack, or heroin can be a very expensive habit, and the only way that most people can maintain such expensive behavior is to turn to dealing. As we say elsewhere in this book, cocaine and opiates can be extremely reinforcing, and they are also expensive in the quanti­ties that habitual users consume. The combination of dependence and expense often leads users to become dealers until they are stopped by medical intervention, arrest, or death.
What does this have to do with the average reader of this book? Any­one who can read this book no doubt has the ability to do honest and legal work and have a successful life. Such a reader might feel that she is above being caught, or just not in the "wrong" circle of friends. This
naiveté might be the most dangerous attitude of all, because, like most jobs, illegal drug dealing depends on knowledge, skills, and having a network of people. Most casual dealers do not have the knowledge or, fortunately, are not willing to do what is necessary to involve themselves fully in the drug culture. Thus, they approach the whole issue as ama­teurs, and like many amateurs in anything, they fail miserably. Only in this case, the stakes are much higher. They can get caught, lose a lot of
money, become victims of criminal violence, or become heavily depen­dent on the substance they are dealing.
As we all know, some people think they have few opportunities and only a short time to live. They will deal drugs no matter what anyone says. In their lives they see jail time as just the cost of doing business. However, a district attorney who has prosecuted thousands of drug cases had just one bit of advice: people with families, an opportunity for education, and a supportive network of friends have so much to lose from being on the wrong side of the legal system that they should never become involved with it. A felony conviction can strip a person of so many opportunities in this society and can cost families so much in
pain, suffering, and financial loss that no amount of money or drug experience is worth the risk.

PHYSICAL AND PSYCHOLOGICAL PROBLEMS

03 Temmuz
PHYSICAL AND PSYCHOLOGICAL PROBLEMS

LSD, psilocybin, and mescaline do not generally cause dangerous phys­ical reactions; and blood pressure, body temperature, and other vital signs remain reasonably stable unless there are acute anxiety reactions. A user is in little danger of seizures or coma. Furthermore, there is lit­tle evidence that these drugs activate the pleasure centers, and addic­tion and physical dependence do not occur. In this sense, they are remarkably safe. However, the psychological consequences for some users can be extreme. The bad trip, in which the drug user feels acute anxiety and perhaps fears that he will not be able to return, is the most common. Fortunately, this reaction ends as the drug is eliminated from the body. Acute anxiety can usually be treated with a dose of a benzodiazepine (a Valium-like drug—see the "Sedatives" chapter). "Talking down" can be helpful, but it is not always practical. While antipsychotic medications like Thorazine (chlorpromazine) were once popular, they are not always effective on bad trips and, in fact, can make things worse. Now that we understand that many hallucinogens act on serotonin-2 receptors, it's possible that an antagonist (blocking) treatment will become available that would terminate the trip immedi­ately. Research studies show that a 5-HT2 antagonist called ketanserin effectively blocks most psychoactive effects of psilocybin. Such drugs exist but have not yet been investigated or approved for this purpose in the United States. Similarly, the narcotic antagonist naloxone should stop a Salvia trip, but this hasn't been tested yet.
What about the myth that taking LSD will make you crazy? Hallucino­gens can worsen the symptoms of people who are already psychotic, but we don't know if they can cause psychosis. They certainly don't very often. However, a number of studies have shown that hallucinogen users are dis­proportionately represented among psychiatric inpatients, and that one to five people out of one thousand who take hallucinogens experience an acute psychotic reaction.
There is a "chicken and egg" problem in understanding this statistic. Most people who are hospitalized for a psychotic reaction to hallucino­gens have never before been seen by a psychiatrist. So, it is impossible to know whether they were completely healthy before the drug experience We do know that a small number of people have very serious reactions to LSD and similar drugs, including prolonged psychotic states. Also, people with a family history of, or other predisposition toward, mental illness should be particularly careful. Sometimes a hallucinogenic experience can bring out symptoms in such individuals

BRAIN AND BEHAVIOR

09 Mayıs
BRAIN AND BEHAVIOR

Once alcohol has been absorbed and distributed, it has many different effects on the brain and behavior. To a large extent these effects vary with the pattern of drinking. Therefore, we discuss the effects of acute, chronic, and prenatal alcohol exposure separately.
ACUTE EXPOSURE
Effects on Behavior and Physical State


Although the effects that a given dose of alcohol will have on an individ­ual vary considerably, the following table shows the general effects of a range of alcohol doses:
Still, there is often a substantial difference between being impaired and appearing impaired. In one study, trained observers were asked to rate whether a person was intoxicated after drinking. At low blood alcohol con­centrations (about half the legal limit for intoxication), only about 10 per­cent of the drinkers appeared intoxicated, and at very high concentrations (greater than twice the legal limit), all of the drinkers appeared intoxicated. However, only 64 percent of people who had blood alcohol concentrations of 100-150 mg/100 ml (well above the legal limit in most states) were judged to be intoxicated. So, in casual social interactions, many people who are significantly impaired—and who would pose a real threat behind the wheel of a car—may not appear impaired even to trained observers.
Alcohol and Brain Cells

You've probably heard some variation of the following statement: "Every time you take a drink of alcohol you kill ten thousand brain cells." Although it is highly unlikely that anyone would drink enough alcohol in a given sitting to kill brain cells directly, as with many such generaliza­tions there is a grain of truth in the warning.
One way that researchers have tried to determine which brain regions control which behaviors in animals is by destroying, or lesioning, a specific brain region and then testing the animal on a particular behavioral task.

Early in the use of this lesioning technique, some researchers found that if they injected a very high concentration of alcohol into the brain (far higher than would be achieved by a drinking person), the cells in that region would die. There is also another grain of truth in the warning about alcohol and brain cells: chronic, repeated drinking damages and sometimes kills the cells in specific brain areas. And it turns out that it might not take a very long history of heavy drinking to do so. We will address this in the "Chronic Exposure" section of this chapter.
There are fundamentally only two types of actions that a chemical can have on nerve cells—excitatory or inhibitory. That is, a drug can either increase or decrease the probability that a given cell will become active and communicate with the other cells to which it is connected. Alcohol generally depresses this type of communication, or synaptic activity, and thus its actions are similar to those of other sedative drugs, like barbiturates (such as phenobarbital) and benzodiazepines (such as Valium). Despite this general suppression of neuronal activ­ity, however, many people report that alcohol activates or stimulates them, particularly soon after drinking, when the concentration of alcohol in the blood is increasing. Although we don't know exactly why alcohol produces feelings of stimulation, there are a couple of possibilities. First, there is the biphasic action of alcohol. This refers to the fact that at low concentrations alcohol actually activates some nerve cells. As the alcohol concentration increases, however, these same cells decrease their firing rates and their activity becomes sup­pressed. Or it might be that some nerve cells send excitatory signals to the other cells with which they communicate, prompting them to send inhibitory messages, actually suppressing the activity of the next cell in the circuit. So, if alcohol suppresses the activity of one of these "inhibitory" cells, the net effect in the circuit would be one of activa­tion. Whatever the exact mechanism, it appears that there are several ways in which alcohol can have activating as well as suppressing effects on neural circuits.
Effects on Specific Neurotransmitters GABA and Glutamate

For many years it was generally thought that alcohol treated all nerve cells equally, simply inhibiting their activity by disturbing the structure of the membrane that surrounds each cell. In this sense the effects of alcohol on the brain were thought to be very nonspecific. However, it is now clear that alcohol has specific and powerful effects on the function of at least two particular types of neuronal receptors: GABA receptors and glutamate receptors. GABA and glutamate are chemical neu­rotransmitters that account for much of the inhibitory and excitatory activity in the brain. When the terminals of one cell release GABA onto GABA receptors on the next cell, that cell becomes less active. When glutamate lands on a glutamate receptor, that cell becomes more active. It is in this way that many circuits in the brain maintain the delicate balance between excitation and inhibition. Small shifts in this balance can change the activity of the circuits and, ultimately, the functioning
of the brain.
Alcohol increases the inhibitory activity of GABA receptors and decreases the excitatory activity of glutamate receptors. These are the two primary ways alcohol suppresses brain activity. While the enhance­ment of GABA activity is probably responsible for many of the general sedating effects of alcohol, the suppression of glutamate activity may have a more specific effect: impairment in the ability to form new memo­ries or think in complex ways while intoxicated. We know that the activ­ity of a particular subtype of glutamate receptor, called the NIVIDA receptor, is very powerfully inhibited by alcohol—even in very low doses. The NMDA receptor is also known to be critical for the formation of new memory. Alcohol's powerful suppression of activity at the NMDA recep­tor may therefore account Mr the memory deficits that people experience after drinking. Dopamine
The neurotransmitter dopamine is known to underlie the rewarding effects of such highly addictive drugs as cocaine and amphetamine. In fact, dopamine is thought to be the main chemical messenger in the reward centers of the brain, which promote the experience of pleasure. Alcohol drinking increases the release of dopamine in these reward cen­ters, probably through the action of GABA neurons, which connect to the dopamine neurons. Studies in animals show that the increase in dopa­mine activity occurs only while the concentration of alcohol in the blood is rising—not while it is falling. So, during the first minutes after drinking the pleasure circuits in the brain are activated, but this "dopamine rush"
disappears after the alcohol level stops rising. This may motivate the drinker to consume more alcohol to start the pleasure sequence again—"chasing the high." The problem is that although the dopamine rush is over, there is still plenty of alcohol in the body. Continued drink­ing in pursuit of the pleasure signals could push the blood alcohol con­centration up to dangerous levels.

Effects on Memory


One of the most common experiences people report after drinking is a failure to remember accurately what happened "the night before." In more extreme cases, after heavy drinking, people often report that whole chunks of time simply appear to be blank, with no memory at all having been recorded. This type of memory impairment is often called a "blackout." (Less extreme versions of this type of memory loss have been called "brown outs" or "gray outs," in which the person may have only very hazy or incomplete memory for the events that occurred during the period of intoxication. In these instances, and even in black­outs, the drinker may remember more about events when reminded of them.) In the past, blackouts were thought to be relatively rare and were viewed as a strong indicator of alcoholism by many clinicians. However, it turns out that blackouts are far more common than previously thought and don't just occur in people with serious alcohol problems. Researchers are now beginning to look more closely at how and when blackouts occur, and there appear to be some disturbing trends. First of all, blackouts appear to be quite frequent among college students, with as many as 40 percent reporting them. But it's not just the memory loss that's disturbing--it's what happens during the periods for which no new memories are made. In one survey, students reported that after a night of heavy drinking they later learned about sexual activity, fights with friends, and driving, for which they had no memory at all. So it seems that blackouts may well be a serious health risk over and above the direct effects that alcohol has on the brain. Sadly, many people joke about blackouts as an embarrassingly funny result of heavy drinking. But they are no joke. Think about it this way: anything that impairs brain function enough to interrupt memory formation is very danger­ous. If it were a blow to the head, exposure to a toxic chemical, or a buildup of pressure in the brain that caused the blackout, it would be taken very seriously. Alcohol-induced blackouts should be taken seriously as well. Short of blackouts, though, it is also clear that alcohol impairs the ability to form new memories even after relatively low doses. Therefore, having a couple of beers while studying for an exam or pre­paring for a presentation at work is probably not a good strategy. The alcohol may promote relaxation, but it will also compromise learning and memory.

Hangover

One of the best-known symptoms of a hangover is a pounding head­ache. The cause is not exactly clear, but it is probably related to the effects of alcohol on blood vessels and fluid balances in the body. In any case, it is much easier to prevent the onset of pain than it is to relieve the pain once it has started. Therefore, the sooner a pain reliever is taken, the better. Some people take one before going to bed after a night of drinking. This way the chemicals in the pain reliever can prevent the pain signals in the brain from getting started as the alcohol is elimi­nated from the body. However, Tylenol (acetaminophen) should not be taken to treat a hangover because it can interact in a very dangerous way with alcohol and its by-products and damage the liver in some peo­ple. Aspirin or ibuprofen can be used instead, but both of these drugs can irritate the stomach and small intestine and together with alcohol may cause gastric upset.
The upset stomach and nausea associated with a hangover are harder to deal with. These may be caused by the toxic by-products of alcohol elimi­nation, irritation to the stomach, or both. No medicines treat these effects specifically. Rather, the best strategy is to eat foods that are gentle on the stomach and to drink plenty of fluids. Morning coffee may help to start the day after a night on the town, but its irritating effects on the stomach may make it an unpleasant waking. And because caffeine is a diuretic, it may also contribute to the dehydration that often accompanies alcohol drinking.

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