Evaluation of socio-demographic factors, behavior and perception about drugs of abuse among students of private universities in Dhaka city
1.1 Drug abuse
Drug abuse or substance abuse is the use of any chemical substance especially controlled substances such as psychoactive drugs, narcotics, hormones, prescription medication or over the counter medicines in a way that society deems harmful to the user or others. A person who abuses a drug uses illegal drugs, or uses legal drugs in a manner that conflicts with the directions given by a physician. Abused drugs include narcotic pain medications, marijuana, heroin, cocaine, sedative, stimulants, and drugs that cause hallucinations. Physical dependence on a drug is called drug dependency. Psychological dependency results in drug addiction. 
Drug abuse is most commonly associated with addictive substances. Alcohol is also addictive and prone to abuse; however, the term alcohol abuse is generally used distinctly from “drug abuse. Some of the most commonly abused drugs are alcohol; nicotine; marijuana; amphetamines; barbiturates; cocaine; methaqualone; opium alkaloids; synthetic opioids; benzodiazepines, including flunitrazepam (Rohypnol); gamma-hydroxybutyrate; 3,4-methylenedioxymethamphetamine (MDMA, ecstasy); phencyclidine; ketamine; and anabolic steroids. Drug abuse may lead to organ damage, addiction, and disturbed patterns of behavior. Some illicit drugs, such as heroin, lysergic acid diethylamide, and phencyclidine hydrochloride, have no recognized therapeutic effect in humans. Use of these drugs often incurs criminal penalty in addition to the potential for physical, social, and psychological harm. 
1.2 Prescription drug abuse
Prescription drug abuse is the use of a prescription medication in a way not intended by the prescribing doctor. Prescription drug abuse includes everything from taking a friend’s prescription painkiller for your backache to snorting ground-up pills to get high. 
An increasing problem, prescription drug abuse is especially common in young people. The prescription drugs most often abused include painkillers, sedatives for anxiety and sleep disorders, and stimulants for attention-deficit/hyperactivity disorder (ADHD) Identifying prescription drug abuse early can help fix the problem before it becomes more serious or turns into an addiction. 
The easiest way of defining drug abuse is observing that a person uses a drug for something other than a medically prescribed purpose. That is, they have a habit of taking a drug to “get high” or “feel better.” They take more than prescribed amounts. They take the drugs for recreation. Some “drugs” that are used for recreation may not be prescription meds, or over-the-counter medications, or even street drugs. They can be common, everyday chemicals. For example, people inhale glue or solvents to get high. 
People want to have a mood change, to feel good. Professional drug counselors will tell you that any use of illegal drugs is drug abuse. Those drugs are illegal because they are potentially very addictive and harmful to a person’s health. That broadens our definition of drug abuse even more. Therefore, a medical professional prescribes any illegal drug use, or any use of prescription or non-prescription medication use beyond what, or any use of a chemical to get high, is drug abuse. 
There are some drugs that are used to relax, to feel good, to be sociable. Alcohol is the most common drug used in America for this purpose. It’s legal, and if taken in moderation, is not harmful. But alcohol is addictive. Some people say marijuana is not addictive, and therefore should be legal, but researchers have found that marijuana has other harmful effects, even if someone is not “addicted.” People can become psychologically addicted, even if there is no physical dependence. 
Almost any substance can abuse. People abuse cigarettes, caffeine and other common, legal substances every day. Sometimes the line between use and abuse is fuzzy. For example, people might go to the tavern after work and have a couple of drinks with their friends. Is that abuse? Some might argue that it becomes abuse when it becomes a regular, daily occurrence. Too many cigarettes, too much coffee, to many diet sodas. The person determines the line. 
1.3 Causes of prescription drug abuse 
Teens and adults abuse prescription drugs for a number of reasons. Some of these include:
Ø To feel good or get high
Ø To relax or relieve tension (painkillers and tranquilizers)
Ø To reduce appetite (stimulants)
Ø To experiment
Ø To be accepted by peers (peer pressure) or to be social
Ø To be safe it’s a false belief that prescription drugs are safer than street drugs
Ø To be legal it’s a mistaken thought that taking prescription drugs without a prescription is legal
Ø To feed an addiction
1.4. Vital Statistics 
Today there are about 190 million drug users around the world.
Ø Drug use has been increasing among the young people worldwide. Most drug abusers are under the age of 30
Ø In 1999, the number of countries reporting injecting drug use was 136, up from 80 in 1992. Of these, 93 Countries also identified HIV among drug injectors.
Ø Cannabis is the most widely abused drug in all parts of the world
Ø The full economic cost of drug abuse in the United States is estimated at approximately $70 billion annually.
Ø Cocaine abuse among the unemployed in Columbia was found to be 10 times higher than among those working.
Ø The illicit drug industry is now estimated to be over $400 billion per year.
1.5 Common signs and symptoms of drug abuse 
Ø You are neglecting your responsibilities at school, work, or home (e.g. flunking classes, skipping work, neglecting your children) because of your drug use.
Ø You’re using drugs under dangerous conditions or taking risks while high, such as driving while on drugs, using dirty needles, or having unprotected sex.
Ø Your drug use is getting you into legal trouble, such as arrests for disorderly conduct, driving under the influence, or stealing to support a drug habit.
Ø Your drug use is causing problems in your relationships, such as fights with your partner or family members, an unhappy boss, or the loss of old friends.
Ø Common signs and symptoms of drug addiction
Ø You have built up a drug tolerance. You need to use more of the drug to experience the same effects you used to with smaller amounts.
Ø You take drugs to avoid or relieve withdrawal symptoms. If you go too long without drugs, you experience symptoms such as nausea, restlessness, insomnia, depression, sweating, shaking, and anxiety.
Ø You have lost control over your drug use. You often do drugs or use more than you planned, even though you told yourself you wouldn’t. You may want to stop using, but you feel powerless.
Ø Your life revolves around drug use. You spend a lot of time using and thinking about drugs, figuring out how to get them, and recovering from the drug’s effects.
Ø You have abandoned activities you used to enjoy, such as hobbies, sports, and socializing, because of your drug use.
Ø You continue to use drugs, despite knowing it’s hurting you. It’s causing major problems in your life—blackouts, infections, mood swings, depression, paranoia—but you use anyway.
1.6 Effects of drug
Drugs can be harmful in a number of ways, through both immediate effects and damage to health over time. Even occasional use of marijuana affects cognitive development and short-term memory. In addition, the effects of marijuana on perception, reaction and coordination of movements can result in accidents. Hallucinogens (such as LSD) distort perceptions, alter heart-rate and blood pressure and, in the long term, cause neurological disorders, depressions, anxiety, visual hallucinations and flashbacks. Cocaine and amphetamines first cause tremors, headaches, hypertension and increased heart rate. 
Long-term effects are nausea, insomnia, and loss of weight, convulsions and depression. Heroin use initially results in nausea, slow respiration, dry skin, itching, slow speech and reflexes but, over a long period, there is the serious risk of developing physical and psychological dependence, which in the end can lead to acute overdose, which can lead to death due to respiratory depression. There is some tendency towards presenting some drugs (such as cannabis and ecstasy) as less harmful than they actually are, without taking into consideration their long-term effects and the effects they have on adolescent development, especially of certain critical cognitive functions like the capacity to memorize. 
While ecstasy is said to have little or no side effects, studies show that its use alters, perhaps permanently, certain brain functions and damages the liver and other body organs. Although not listed as illicit, inhalants are widely abused, especially by disadvantaged youth. Some of these volatile substances, which are present in many products such as glue, paint, gasoline and cleaning fluids, are directly toxic to the liver, kidney or heart, and some produce progressive brain degeneration. 
The major problem with psychoactive drugs is that when people take them, they focus on the desired mental and emotional effects and ignore the potentially damaging physical and mental side effects that can occur. There is no illicit drug that can be considered safe. In one way or another, the use of psychoactive substances alters the normal functioning of the human body, and in the long run, can cause serious damage .
1.6.1 Physical warning signs of drug abuse 
Ø Bloodshot eyes or pupils that is larger or smaller than usual.
Ø Changes in appetite or sleep patterns.
Ø Sudden weight loss or weight gain.
Ø Deterioration of physical appearance and personal grooming habits.
Ø Unusual smells on breath, body, or clothing.
Ø Tremors, slurred speech, or impaired coordination.
1.6.2 Behavioral signs of drug abuse 
Ø Drop in attendance and performance at work or school.
Ø Unexplained need for money or financial problems may borrow or steal to get it.
Ø Engaging in secretive or suspicious behaviors
Ø Sudden change in friends, favorite hangouts, and hobbies
Ø Frequently getting into trouble (fights, accidents, illegal activities)
1.6.3 Psychological warning signs of drug abuse 
Ø Unexplained change in personality or attitude
Ø Sudden mood swings, irritability, or angry outbursts
Ø Periods of unusual hyperactivity, agitation, or giddiness
Ø Lack of motivation; appears lethargic or “spaced out.
Ø Appears fearful, anxious, or paranoid, with no reason
1.7 Causes of drug abuse
When we take drugs, for either medical purposes or recreation, there is a benefit or reward that we are trying to achieve. For example, pain medication is intended to bring relief to an injured or stressed area of our body. The beginning stages of drug abuse causes us to crave more and to use more. The unintended consequences of that is our need to take more and more of the drug to get the same result. 
Many factors can cause drug addiction. However, with the right drug addiction treatment, anybody can be reformed to lead a healthy, productive life. Drug abuse causes the pathways inside the brain to be altered. The drug brings on physical changes in the nerve cells. These cells (neurons) communicate with each other releasing neurotransmitters into the gaps or synapses between the nerve cells. This makes some drugs are more addictive than others are. Several other factors contribute to drug abuse. We’ll go into greater detail on another page, but for now the major factors are one’s genetic makeup, personality and peer pressure. Again, we will explain these as we go along. 
1.8 Obtaining prescription drugs
Most prescriptions are written for people who have a true medical need for these drugs. But many households have a drawer or cabinet filled with old prescription bottles containing leftover drugs. Because prescription drugs have medical uses, teens often believe these drugs are a safe alternative to street drugs. In some cases, a doctor’s prescription is not even needed. Some countries do not require prescriptions for opioid painkillers or other commonly abused drugs, so they can be obtained from some websites without a prescription. Obtaining drugs online from pharmacies that do not require a prescription can be risky. Some websites sell counterfeit drugs that contain potentially dangerous substances. 
1.9 Risk Factors of drug abuse
We are all a product of our parents. If your parents have addiction struggles, chances are you are more susceptible to addiction. That is, why drug abuse is more common in some families than in others. If your parents smoke, chances are good you will smoke. If your parents used alcohol, probably follow and use that drug in much the same way. If your father was an alcoholic, you have a predisposition to abusing that drug. Drug abuse causes one generation to pass it on to the next. 
Aside from the inherited factors, some people have a personality that is more likely to become drug dependent. People are curious, so that alone can lead a person to try a drug. We experiment and see what happens. We are looking to relax and have pleasure. We all want to feel good, and we are by nature impatient. Drugs give us an instant gratification that other things do not, so for that moment or hour of for whatever timeframe, we feel good. We want what we want. Someone diagnosed with depression, attention deficit disorder, or hyperactivity. Maybe there has been some stress, or anxiety in their life. Whatever the case, these are contributing factors. Even some common personality characteristics, such as aggression, may be a factor. Children who do not have confidence, healthy self-esteem may be prone to turning to drugs to fill the void. Drug abuse causes negative changes in personality that can lead to an even more destructive behavior. 
We are all wired to have relationships, and sometimes those relationships cause us to give in to something we otherwise would avoid in order to maintain the relationship. Peer pressure is huge and nowhere is this greater than during our teenaged years. Kids want to be cool. It begins as a social action, to take the drugs to be a part of the group, to be accepted. It’s not just teenagers, as peer pressure takes so many different forms. There is social etiquette, for example, to take a drink during a party. “I’m a social drinker.” How many times have you heard that? Some people actually believe that drug abuse causes you to be accepted and part of the ‘popular’ group. 
If one wants to get drugs, he or she will not have to look far because they are everywhere. High school students can tell you this. Drug abuse causes people to sell drugs to the most vulnerable population, children. It is not just the stereotypical poor sections of the inner city that serve as the hotbed for drugs. Drugs are found in suburban shopping malls, rural schools, and well-to-do private school, on the job in factories, offices and remote job sites. 
We include this heading because we want to stress that there is no data to support any claim that one race of people or any particular cultural group is more prone to drug abuse than another. Drug abuse is a human problem and crosses all boundaries. Drug abuse causes do not include race. 
We want to feel good physically and emotionally. Sometimes drugs are the substitution for a healthy life experience. The person in pain and they want to numb the pain. The drug numbs the pain and for a moment, they do not feel as poorly. The person needs to escape the pain of the life experience, and for a short while, the drug takes them away and they feel better. 
Sometimes people need some help coping with life. Everyday life becomes a struggle and simple things become too much to handle. Drugs are used to deal with it. In the case of addiction, we are not talking about the use of medication, under the care and observation of a doctor. People who have been clinically diagnosed with anxiety can lead a very good life. We’re talking here about people who just need to escape. Their drug of choice facilitates that escape. 
1.10 Types of Drug abuse
When talking about causes and factors leading to drug abuse, it is necessary to take a moment and look at the various types of drugs. As we mentioned before, these all have their characteristics. 
· Cannabis Compounds: The most common drug in this category is marijuana, which produces a high for the user
· Depressants: Alcohol is the most common depressant, as everything slows, as evidenced by the documented testing of people’s reflexes while driving a car under the influence.
· Stimulants: Amphetamines come to mind quickly, but a more common stimulant is nicotine.
· Hallucinogens: LSD was a popular drug in the 1960’s
· Designer Drugs: Ecstasy is popular with the rave set.
· Inhalants: Glue sniffing or the improper use of other common, store-bought chemicals for getting high is an everyday occurrence. Single Moms are over-worked and over-stressed read how that can cause addiction. Nicotine is also a leading cause of addiction death around the world. 
1.11 Drug addiction
Addiction is a chronic, often relapsing brain disease that causes compulsive drug seeking and use despite harmful consequences to the individual who is addicted and to those around them. Drug addiction is a brain disease because the abuse of drugs leads to changes in the structure and function of the brain. Although it is true that for most people the initial decision to take drugs is voluntary, over time the changes in the brain caused by repeated drug abuse can affect a person’s self control and ability to make sound decisions, and at the same time send intense impulses to take drugs. 
It is because of these changes in the brain that it is so challenging for a person who is addicted to stop abusing drugs. Fortunately, there are treatments that help people to counteract addiction’s powerful disruptive effects and regain control. 
Research shows that combining addiction treatment medications, if available, with behavioral therapy is the best way to ensure success for most patients. Treatment approaches that are tailored to each patient’s drug abuse patterns and any co-occurring medical, psychiatric, and social problems can lead to sustained recovery and a life without drug abuse.  The word addiction means getting habituated with something. In case of drugs when a human body gets dependent on some stimulating things, and after a certain period it creates a habit, which means that the body has become dependent on the stimulant, which is addiction.  World Health Organization (WHO) defines it: Drug is a chemical substance of synthetic, semi synthetic or natural origin intended for diagnostic, therapeutic or palliative use or for modifying physiological functions of man and animal. 
Addiction is a complex disorder characterized by compulsive drug use. People who are addicted feel an overwhelming, uncontrollable need for drugs or alcohol, even in the face of negative consequences. This self-destructive behavior can be hard to understand. The answer lies in the brain. Repeated drug use alters the brain causing long-lasting changes to the way it looks and functions. These brain changes interfere with your ability to think clearly, exercise good judgment, control your behavior, and feel normal without drugs. These changes are also responsible, in large part, for the drug cravings and compulsion to use that make addiction so powerful. Addiction is influenced by a person’s biology, social environment, and age or stage of development. The more risk factors an individual has, the greater the chance that taking drugs can lead to addiction. 
The genes that people are born with in combination with environmental influences — account for about half of their addiction vulnerability. Additionally, gender, ethnicity, and the presence of other mental disorders may influence risk for drug abuse and addiction. Many studies show how alcohol affects the brain and many of the physical aspects of the body. What this article seeks to explain is the body systems that are tied to addiction. There are many different reasons that a person might initially become alcohol dependent. A person might drink because he or she is impulsive, stressed, depressed or seeking some form of pleasure experience. Once a drinking pattern is established, there is a common neurobiology experienced by all people and this article aims to explain some of the neurobiological changes that are involved in addiction. 
1.12.1 The Neurotransmitter System
To understand how alcohol use associated with alcohol dependence affects brain function, it is important to understand how neurons communicate with each other through electrical and chemical signals. Nerve signals are transmitted from one region of the brain to another region of the brain or to the rest of the body through communication between two or more neurons located next to each other. 
When a neuron is activated, an electrical signal is generated which travels along the membrane surrounding the neuron body and the axon – the long extension protruding from the neuron body. When the signal reaches the end of the axon, it triggers the release of neurotransmitters from the cell. These neurotransmitters travel across the narrow space separating one neuron from another. On the signal-receiving neuron, the neurotransmitter molecules then interact with receptors, and this interaction either promotes or prevents the generation of new electrical signals in that neuron, depending on the neurotransmitters involved. 
Many neurotransmitters can have both excitatory and inhibitory effects, depending on which brain region is studied and which receptors are present on the signal-receiving neurons. Neurotransmitters that often have excitatory effects include dopamine, glutamate, and serotonin; the neurotransmitter that primarily has inhibitory effects is gamma-amino butyric acid. Alcohol is said to possess acute positive reinforcing effects because of its interactions with individual transmitter systems within the general reward circuitry of the brain. 
The intracellular events elicited by alcohol can lead to changes in many other neural processes, including those that trigger long-term alcohol effects which eventually lead to tolerance, dependence, withdrawal, sensitization and, ultimately, addiction. The general reward circuitry of the brain centers on connections between the ventral tegmental area and the basal forebrain (which includes the nucleus accumbens, olfactory tubercle, frontal cortex, and amygdala). Because the neurotransmitters help to complete these connections in the brain, they are primary elements in the neurobiological study of addiction. 
1.12.2 Excitatory Neurotransmitters
Neurotransmitters that increase the excitability of neurons and promote the generation of a new nerve signal.
Dopamine is a chemical naturally produced in the body. We depend on our brain’s ability to release dopamine in order to experience pleasure and to motivate our responses to the natural rewards of everyday life, such as social interaction, the sight or smell of food and the immediate reinforcing properties of all drugs of misuse, including alcohol.
Activation of the mesolimbic pathway increases the firing of dopamine neurons in the ventral tegmental area (VTA) of the midbrain and subsequently increases dopamine release into the nucleus accumbens and other areas of the limbic forebrain, such as the prefrontal cortex. Alcohol activates the mesolimbic pathway indirectly, by activating beta-endorphins that innervate the ventral tegmental area and the nucleus accumbens, producing a net effect of excitation as information is transmitted to the dopamine receptors in these brain areas. It is thought that antagonists of dopamine, GABA, opioid, and serotonin, may decrease the rewarding properties of alcohol and drugs of abuse, resulting in reduced consumption. Positron Emission Topography studies have allowed researchers to directly investigate the role of dopamine and the reward system in alcohol consumption in humans. 
1.12.3 The Endogenous Opioid System
Endogenous opioids are small protein molecules (i.e., peptides) formed naturally in the body and chemically related to morphine and heroin. These opioids are produced primarily in the pituitary gland and brain. They apparently act like excitatory neurotransmitters to stimulate neurons. They are involved in various physiological processes, such as pain relief, stress response, euphoria, and the rewarding and reinforcing effects of various drugs, including alcohol. Three distinct families of endogenous opioids exist: endorphins, enkephalins, and dynorphins. The most potent endogenous opioid is beta-endorphin. 
1.12.4 Endogenous Opioids and Alcohol
One-time alcohol ingestion in both humans and experimental animals may stimulate the release of endogenous opioids in both the brain and the rest of the body. Thus, the body may respond to alcohol as if the person had ingested a small quantity of an opioid drug. A special protein called the mu-opioid receptor, which is located in the membranes of nerve cells, detects internal opiate neurotransmitters, such as beta-endorphin, that the brain uses to allow nerve cells to communicate with each other. A specific gene (named OPRM1) encodes the mu-opioid receptor.
1.12.5 The HPA Axis – the stress response system
The hypothalamic-pituitary adrenal (HPA) axis is a hormone system that plays a central role in the body’s stress response. This axis involves hormones that are produced in the brain’s hypothalamus and anterior pituitary gland as well as in the adrenal glands atop the kidneys. This system, which controls a wide variety of metabolic functions, is activated in response to all kinds of stress, both physical and psychological.
1.12.6 The HPA Axis and Alcohol
A person experiencing stress may be more likely to turn to alcohol to find relief (i.e. relief drinking) and thus may be more sensitive to the relieving effects of alcohol creating a pathway to heavy use and even dependence. Ingestion of small amounts of alcohol can biochemically prepares a person to cope with subsequent stress. 
The excitatory neurotransmitter serotonin helps regulate such functions as bodily rhythms, appetite, sexual behavior, and emotional states. Serotonin subtly modifies the function of neurons by interacting with receptors on the neuron’s surface. It is an important modulator within what is called the behavior inhibition system and it is very likely influenced by genetics, and early stress experiences. 
Glutamate exerts its effects by interacting with several types of receptors, including one called the N-methyl-D-aspartate (NMDA) receptor. Alcohol acts on these NMDA receptors, inhibiting their functions and thereby diminishing glutamate-mediated neurotransmission. NMDA receptors may play a role in memory formation. Prenatal, acute, or chronic alcohol exposure may hinder the person’s ability to learn and to retain new information. 
1.12.9 Inhibitory Neurotransmitters
Inhibitory neurotransmitters are neurotransmitters that reduce the excitability of neurons and prevent the generation of a new nerve signal. 
Gamma-aminobutyric acid (GABA) is the primary inhibitory neurotransmitter in the mammalian central nervous system that carries signals between certain nerve cells. It modulates the activity of neurons by binding to GABA-specific receptors (GABAA, GABAB, etc) in their cell membranes and literally inhibiting their ability to respond to signaling. GABA actions are mediated primarily by the GABAA receptor. 
Alcohol and GABA
Alcohol consumption causes motor incoordination and sedation as does high activity of inhibitory neurotransmitters, therefore researchers have suspected that GABA and the GABAA receptor contribute to alcohol’s effects on the brain In a study done in 1995, researchers Nevo and Hamon discovered that alcohol appears to enhance the inhibitory actions of GABA. Chronic alcohol consumption leads to a decline in the number of GABA receptors in the brain and thus reduces GABA’s ability to bind to its receptors. 
It is estimated that 40–60% of the vulnerability to addiction is attributable to genetic factors. Genetic differences in the body’s hormonal responses to stress and alcohol ingestion exists between people. Those differences likely play an important role in determining a person’s sensitivity to alcohol’s pleasurable effects, level of craving for alcohol, and extent of vulnerability to excessive drinking and alcohol dependence. In animal studies, several genes have been identified that are involved in responses to drugs and alcohol, and experimental modification of these genes has reduced the self-administration of drugs and alcohol by the animal subjects. 
1.13 Drugs of abuse
The opiates and their synthetic analogues are the most effective analgesic agents known, and at the same time can produce tolerance, dependence (including somatic dependence), and addiction. Physical dependence on opiates can contribute to addiction, but can also occur independently of it. For example, patients with cancer pain may become physically dependent on these drugs but do not compulsively abuse them. 
Nicotine is the main psychoactive ingredient of tobacco and is responsible for the stimulant effects, reinforcement, and dependence that result from tobacco use. Cigarette smoking rapidly delivers nicotine into the bloodstream. Nicotine differs from cocaine and opiates in that it is powerfully reinforcing in the absence of subjective euphoria. The effects of nicotine are caused by its activation of nicotinic acetylcholine receptors (nAChRs). Nicotinic AChRs are ligand-gated cation channels located both presynaptically and postsynaptically. Presynaptic nAChRs facilitate neurotransmitter release. The reinforcing effects of nicotine depend on an intact mesolimbic dopamine system. Nicotine induced increases in locomotor behavior are also blocked by destruction of mesolimbic dopamine nerve terminals or cell bodies. Moreover, nicotine increases dopamine neurotransmission and energy metabolism in the nucleus accumbens. 
Tetrahydrocannabinol (THC) is the major psychoactive compound contained in marijuana. THC produces fects in humans that range from mild relaxation, euphoria, analgesia, and hunger to panic attacks. Reinforcing effects of cannabinoids comparable to those of other addictive drugs have not been demonstrated in animals, but cannabinoids have been shown to decrease reward thresholds andpromote conditioned place preference in rats. THC increases mesolimbic dopamine transmission in the NAc shell, probably via a opioid receptor-mediated mechanism because receptor antagonists prevent the THCinduced dopamine increases in the brain mesolimbic area . Cannabinoids have also been reported to inhibit excitatory glutamatergic neurotransmission in the substantia nigra pars reticulate. 
Phencyclidine (PCP or angel dust)and ketamine are related drugs classified as dissociative anesthetics. These drugs exhibit psychotomimetic properties, but are distinguished from hallucinogens by their distinct pharmacologic effects, including their reinforcing properties and risks related to compulsive abuse. The reinforcing properties of PCP and ketamine are mediated by the binding to specific sites in the channel of the NMDA glutamate receptor, where they act as noncompetitive NMDA antagonists. PCP is self-administered directly into the NAc, where its reinforcing effects are believed to result from the blockade of excitatory glutamatergic input to the same medium spiny NAc neurons inhibited by opioids, and also by increases in extracellular dopamine. In contrast, hallucinogens, such as LSD, act at 5-HT2 serotonin receptors. 
1.14 Effects of Drug on body
Drugs are chemicals that tap into the brain’s communication system and disrupt the way nerve cells normally send, receive, and process information. There are at least two ways that drugs are able to do this: (1) by imitating the brain’s natural chemical messengers, and/or (2) by over stimulating the “reward circuit” of the brain. Some drugs, such as marijuana and heroin, have similar structures to chemical messengers, called neurotransmitters, which are naturally produced by the brain. Because of this similarity, these drugs are able to “fool” the brain’s receptors and activate nerve cells to send abnormal messages. Other drugs, such as cocaine or methamphetamine, can cause the nerve cells to release abnormally large amounts of natural neurotransmitters, or prevent the normal recycling of these brain chemicals, which is needed to shut off the signal between neurons. This disruption produces a greatly amplified message that ultimately disrupts normal communication patterns. 
Nearly all drugs, directly or indirectly, target the brain’s reward system by flooding the circuit with dopamine. Dopamine is a neurotransmitter present in regions of the brain that control movement, emotion, motivation, and feelings of pleasure. The overstimulation of this system, which normally responds to natural behaviors that are linked to survival (eating, spending time with loved ones, etc), produces euphoric effects in response to the drugs. This reaction sets in motion a pattern that “teaches” people to repeat the behavior of abusing drugs. 
As a person continues to abuse drugs, the brain adapts to the overwhelming surges in dopamine by producing less dopamine or by reducing the number of dopamine receptors in the reward circuit. As a result, dopamine’s impact on the reward circuit is lessened, reducing the abuser’s ability to enjoy the drugs and the things that previously brought pleasure. This decrease compels those addicted to drugs to keep abusing drugs in order to attempt to bring their dopamine function back to normal. And, they may now require larger amounts of the drug than they first did to achieve the dopamine high an effect known as tolerance. 
Long-term abuse causes changes in other brain chemical systems and circuits as well. Glutamate is a neurotransmitter that influences the reward circuit and the ability to learn. When the optimal concentration of glutamate is altered by drug abuse, the brain attempts to compensate, which can impair cognitive function. Drugs of abuse facilitate nonconscious (conditioned) learning, which leads the user to experience uncontrollable cravings when they see a place or person they associate with the drug experience, even when the drug itself is not available. Brain imaging studies of drug-addicted individuals show changes in areas of the brain that are critical to judgment, decisionmaking, learning and memory, and behavior control. Together, these changes can drive an abuser to seek out and take drugs compulsively despite adverse consequences in other words, to become addicted to drugs. 
1.15 Myths about Drug Addiction and Substance Abuse
MYTH 1: Overcoming addiction is a simply a matter of willpower. You can stop using drugs if you really want to. Prolonged exposure to drugs alters the brain in ways that result in powerful cravings and a compulsion to use. These brain changes make it extremely difficult to quit by sheer force of will. 
MYTH 2: Addiction is a disease; there’s nothing you can do about it. Most experts agree that addiction is a brain disease, but that doesn’t mean you’re a helpless victim. The brain changes associated with addiction can be treated and reversed through therapy, medication, exercise, and other treatments. 
MYTH 3: Addicts have to hit rock bottom before they can get better. Recovery can begin at any point in the addiction process—and the earlier, the better. The longer drug abuse continues, the stronger the addiction becomes and the harder it is to treat. Don’t wait to intervene until the addict has lost it all. 
MYTH 4: You can’t force someone into treatment; they have to want help. Treatment doesn’t have to be voluntary to be successful. People who are pressured into treatment by their family, employer, or the legal system are just as likely to benefit as those who choose to enter treatment on their own. As they sober up and their thinking clears, many formerly resistant addicts decide they want to change. 
MYTH 5: Treatment didn’t work before, so there’s no point trying again; some cases are hopeless. Recovery from drug addiction is a long process that often involves setbacks. Relapse doesn’t mean that treatment has failed or that you’re a lost cause. Rather, it’s a signal to get back on track, either by going back to treatment or adjusting the treatment approach. 
1.16 Stages of addiction
Addiction has some stages
a) Initial stage
b) Pre-mature stage
c) Mature stage and
d) Dangerous stage 
1.16.1 Initial stage (starting)
This is the first stage of drug addiction. At first, a person starts to take drug without concerning his body. At the early stage he takes it just normally, and gets the ordinary happiness, which makes him feel better. Sometimes, he wants to touch heavenly excitement and dreams himself as a floating constituent in the sky. This is the first stage of drug abusing. Amateurs are in this group. They take drug once or twice a week with their friends or seniors in their locality, who are already addicted. He collects it and processes it to take. 
1.16.2 Pre-mature stage (the real test of drug)
In this stage, drugs become a habit, and the abuser wants more. Feeling better, s/he tries to increase the dosage drugs. It is taken at least 4-5 times a week. This is the primary stage for abusers in becoming addicted. At the initial stage they can easily manage or collect the money for purchasing. They collect money from their family, and sometimes from other sources. They take drugs with their friends. After a few days they need to take more and become dependent on it both mentally and physically. The sudden need for excess money, involves them in criminal acts like hijacking, and they feel thrilled to do it. 
1.16.3 Mature stage
After the pre-mature stage, abusers become seriously addicted. They have to take it every day, after a certain period. In maximum of cases, it is taken from evening to night time. For that, they are busy all day long in collecting the expenditure of drug. They need much more money for it and sometimes they turn against the law. Many discontinue their education after failing to concentrate on any kind of discipline. They forget social protocol, always remain bad tempered and feel they are always in the right. They do not want to hear any advice and count themselves as very aware and competent. Sometimes they feel frustrated and even lose the will to live. 
1.16.4 Decaying stage
After mature stage, most of the abusers stay on the verge of decaying. It means gradually their lives crumble. They can realize how imbalanced they are. They lose taste for food. At this stage they become fully dependent on drug, gradually after a few hours they have to take it, otherwise their body system stops. In that situation the abuser loses human characteristics and behaves like a monster. They have no sense to evaluate good or bad, to enjoy anything; they lose interest in normal male/female yeaning. Finally, one day they fully surrender to drugs, which lead them to their graves. 
1.17 Causes of addiction
People abuse drugs for a number of different reasons. The most common reason why people abuse drugs is to “get high.” Adolescents and preadolescents can become involved in experimentation with drugs. However, only a small percentage of people who experiment with drugs become drug abusers. The desire to get high may be from an underlying disease such as depression. It may also come from the pressures of coping with school, work, or family tensions. Drug abuse by pregnant women results in the developing fetus (baby) being exposed to these same drugs. The baby may develop birth defects. The baby may be born with an addiction and go into withdrawal. The baby may be born with a disease associated with drug abuse such as HIV/AIDS. People with specific medical conditions, such as chronic pain from cancer, can become dependent on certain drugs but not addicted in the sense they would steal a stereo to pay for the drugs. Many psychiatric diseases can be complicated by substance abuse. Similarly, drug abuse may be a sign of a more serious mental health problem. 
Athletes have abused a variety of agents, such as steroids, to enhance muscle mass or improve athletic ability. Athletes have also abused amphetamines to make them feel more powerful and to mask pain so they can continue to play even with injuries. Drug testing programs have reduced this problem to some extent, but drug use among athletes is still a problem worldwide. 
1.18 Drug Dependence & Abuse Symptoms
The signs and symptoms displayed by a person depend on what substances the person has abused. A person who has not abused drugs extensively may experience unpleasant symptoms and may seek help from family members and friends. Chronic drug abusers generally know what to expect from their drug use and rarely seek help for themselves. Most agents cause a change in level of consciousness—usually a decrease in responsiveness. A person using drugs may be hard to awaken or may act bizarrely. Suppression of brain activity can be so severe that the person may stop breathing, which can cause death. Alternatively, the person may be agitated, anxious, and unable to sleep. Hallucinations are possible. Abnormal vital signs (temperature, pulse rate, respiratory rate, blood pressure) are possible and can be life threatening. Vital sign readings can be increased, decreased, or absent completely.
Sleepiness, confusion, and coma are common. Because of this decline in alertness, the drug abuser is at risk for assault or rape, robbery, and accidental death. Skin can be cool and sweaty, or hot and dry. Chest pain is possible and can be caused by heart or lung damage from drug abuse. Abdominal pain, nausea, vomiting, and diarrhea are possible. Vomiting blood, or blood in bowel movements, can be life threatening. Withdrawal syndromes are variable depending on the agent but can be life threatening. Sharing IV needles among people can transmit infectious diseases, including HIV (the virus that causes AIDS) and hepatitis types B and C. 
Many common household drugs and chemicals can be abused. Gasoline and other hydrocarbons are frequently abused by adolescents and preadolescents. Over-the-counter drugs, such as cold medications, are commonly taken in excessive doses by adolescents and young adults to get high. Prescription medications are additional examples of drugs that are abused and that can be obtained illegally (without a prescription). Amphetamines and cocaine cause impotence in men. Cocaine and amphetamine users to counteract impotence have used Sildenafil (Viagra). Because Viagra is generally prescribed for middle-aged and older men, a younger person must be questioned as to why he has a need for Viagra. 
1.19 Ways of taking substance as a drug
Substances can be taken into the body in several ways:
Ø Oral ingestion (swallowing)
Ø Inhalation (breathing in) or smoking
Ø Injection into the veins (shooting up)
Ø Depositing onto the mucosa (moist skin) of the mouth or nose (snorting) 
1.20 Drug Dependence & Abuse Treatment
Self-Care at Home
If a drug has been ingested inappropriately, contact a local chapter of the American Association of Poison Control Centers. Visiting an emergency department is usually appropriate to obtain proper treatment. Home care is not appropriate if the drug of abuse cannot be identified. People who have ingested unknown drugs should be taken to the emergency department. People with severe symptoms should not be treated at home. They should be taken directly to the emergency department. The key to treatment is stopping the abuse of the drugs or substances. Agitated or violent people need physical restraint and may need sedating medications in the emergency department until the effects of the drugs wear off. This can be disturbing for the person to experience and for family members to witness. Medical professionals go to great lengths to use as little force and as few medications as possible. 
It is important to remember that whatever the medical staff does, it is to protect the person. Very few antidotes are available for drug intoxications. In most cases, the only way to eliminate a drug is for the body to metabolize it—in other words, let it run its course. In some acute intoxications, the doctor may administer certain agents to help prevent absorption in the stomach or to help speed metabolism of the drug. The dose of some agents (for example, benzodiazepines and barbiturates) must be reduced slowly to prevent withdrawal. Withdrawal from some drugs can cause significant problems, and stopping these drugs should only be done under the supervision of an appropriate health care provider. 
Withdrawal from other agents, such as narcotics, is uncomfortable but generally not harmful and unpleasant effects can be lessened with prescription medications. These prescriptions must be combined with a specific plan for stopping drug abuse. The use of the prescription medication combined with continued drug abuse may cause life-threatening complications.
People who are acutely intoxicated may need hospitalization for detoxification. Some cities have detoxification centers for sobering from drug and alcohol intoxication. Counseling programs may be suggested. Programs similar to Alcoholics Anonymous, such as those listed through the Web of Addictions, are helpful for some. 
The initial evaluation by a doctor is just the first step in battling drug abuse. Follow-through in drug avoidance is essential to successful treatment. It will generally be necessary to discharge the person from the emergency department into the care of a sober adult. Activities that require skill and judgment, such as driving, high-speed activities (bicycling, skateboarding), operating machinery, and swimming (even bathtub use) should not be undertaken until all the effects of the drug have worn off. Joining support groups like Alcoholics Anonymous or Narcotics Anonymous can be intimidating, but such groups are very helpful for some people. A social worker at the hospital can advise on local resources available. 
Prevention involves avoiding places frequented by drug abusers and not associating with known drug abusers. Knowledge about drug use and abuse is key to preventing abuse in the first place and avoiding relapse among those who are recovering. 
Treatment of drug dependence and abuse requires a long-term outlook. A person who has abused drugs in the past must be constantly vigilant never to use them again. Relapses are common. Family and friends must provide support with a caring attitude during these relapses. 
1.21 Some Findings from other survey
1. Opinion on how the respondents were drug abused
· Encouragement from friends
· Frustration from family matters
· To get immediate relief from tension
2. Reasons for being addicted to drugs
· Easy access to drugs
· Unemployment problem/economic insolvency
· Surrounding atmosphere
· Estranged in love
· Mental stress due to family problem
3. Sources of money for buying drugs
· From own income
· From pocket money
· Loan from friends, family members
· Collect money by criminal activities like hijacking, extortion etc.
4. Where from respondents collect drugs/the nearest drug spots
· Specific sellers in the locality
· Drug smugglers in town
· Houses near border area
· Drug smugglers in border crossing points
· From police, BDR
· Spots beside lanes/roads
5. Persons involved in drug business/smuggling: Respondents opinion
· Some elites in society
· Some political leaders/so-called student leaders
· A syndicate of smugglers
· Some members of the police/BDR
6. Causes why respondents change drugs one after another
· A tendency to increase the dose because the same dose doesn’t create the desired effect.
· Impatience in body and insomnia in not having drug after a certain time.
· A psychological and physical dependence on the effects of the drugs.
· to feel better
· Easy access to other drugs
· Lower cost
· Adventure in tasting different drugs
· Desire to have an extreme taste of addiction
7. Negative effects due to drug abusing: Respondents view
· Physical impatience
· Sense of perception doesn’t work
· Increased head-ache
· Feeling dizziness until taking drugs
· Hallucination syndromes
· Decreased working capability and stability
· Sexual problem
· Abnormal behavior
· Loose humanity and every kind of assessment
· Lack of discipline in daily life
8. Suggestions of respondents to get rid of drug addiction
· Personal will is the main way to get rid of addiction
· Creating more employment opportunities
· Ensuring proper treatment and rehabilitation measures
· Healthy drug free working environment
· To involve in any creative work
· To avoid mixing with bad company
· Enactment of articles on anti-drug issues in the text books and newspapers
· Media campaign against drugs
9. Changes in social behavior according to the respondents
· Increased hijacking
· Increased extortion
· Increased stealing, robbery
· Deteriorated law and order situation and respectness to elder
· Increased personal and family expenditure
· Lost of interest in education
· Change in morality
1.22. Addictive behaviors
Any activity, substance, object, or behavior that has become the major focus of a person’s life to the exclusion of other activities, or that has begun to harm the individual or others physically, mentally, or socially is considered an addictive behavior. A person can become addicted, dependent, or compulsively obsessed with anything. Some researchers imply that there are similarities between physical addiction to various chemicals, such as alcohol and heroin, and psychological dependence to activities such as compulsive gambling, sex, work, running, shopping, or eating disorders. 
It is thought that these behavior activities may produce beta-endorphins in the brain, which makes the person feel “high.” Some experts suggest that if a person continues to engage in the activity to achieve this feeling of well-being and euphoria, he/she may get into an addictive cycle. In so doing, he/she becomes physically addicted to his/her own brain chemicals, thus leading to continuation of the behavior even though it may have negative health or social consequences. Others feel that these are just bad habits. 
Most physical addictions to substances such as alcohol, heroin, or barbiturates also have a psychological component. For example, an alcoholic who has not used alcohol for years may still crave a drink. Thus some researchers feel that we need to look at both physical and psychological dependencies upon a variety of substances, activities, and behaviors as an addictive process and as addictive behaviors. They suggest that all of these behaviors have a host of commonalities that make them more similar to that different from each other and that they should not be divided into separate diseases, categories, or problems. 
1.22.1 Common Characteristics among Addictive Behaviors
There are many common characteristics among the various addictive behaviors:
1. The person becomes obsessed (constantly thinks of) the object, activity, or substance.
2. They will seek it out, or engage in the behavior even though it is causing harm (physical problems, poor work or study performance, problems with friends, family, fellow workers).
3. The person will compulsively engage in the activity, that is, do the activity over and over even if he/she does not want to and find it difficult to stop.
4. Upon cessation of the activity, withdrawal symptoms often occur. These can include irritability, craving, restlessness or depression.
5. The person does not appear to have control as to when, how long, or how much he or she will continue the behavior (loss of control). (They drink 6 beers when they only wanted one, buy 8 pairs of shoes when they only needed a belt, ate the whole box of cookies, etc).
6. He/she often denies problems resulting from his/her engagement in the behavior, even though others can see the negative effects.
7. Person hides the behavior after family or close friends have mentioned their concern. (Hides food under beds, alcohol bottles in closets, doesn’t show spouse credit card bills, etc).
8. Many individuals with addictive behaviors report a blackout for the time they were engaging in the behavior (don’t remember how much or what they bought, how much the lost gambling, how many miles they ran on a sore foot, what they did at the party when drinking)
9. Depression is common in individuals with addictive behaviors. That is why it is important to make an appointment with a physician to find out what is going on.
10. Individuals with addictive behaviors often have low self esteem, f