Physical and/or psychological dependency on a psychoactive (mind-altering) substance (e.g., alcohol, narcotics, nicotine), defined as continued use despite knowing that the substance causes harm. Physical dependency results when the body builds up a tolerance to a drug, needing increasing doses to achieve the desired effects and to prevent withdrawal symptoms. Psychological dependency may have more to do with one's psychological makeup; some people may have a genetic tendency to addiction. The most common addictions are to alcohol (see alcoholism), barbiturates, tranquilizers, and amphetamines, as well as to the stimulants nicotine and caffeine. Initial treatment (detoxification) should be conducted with medical supervision. Individual and group psychotherapy are critical elements. Alcoholics Anonymous and similar support groups can increase the success rate of other efforts. The ability to admit addiction and the will to change are necessary first steps.
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The term "addiction" is used in many contexts to describe an obsession, compulsion, or excessive physical dependence or psychological dependence, such as: drug addiction, alcoholism, compulsive overeating, problem gambling, computer addiction, etc.
In medical terminology, addiction is a state in which the body relies on a substance for normal functioning and develops physical dependence, as in drug addiction. When the drug or substance on which someone is dependent is suddenly removed, it will cause withdrawal, a characteristic set of signs and symptoms. Addiction is generally associated with increased drug tolerance. In physiological terms, addiction is not necessarily associated with substance abuse since this form of addiction can result from using medication as prescribed by a doctor.
However, common usage of the term addiction has spread to include psychological dependence. In this context, the term is used in drug addiction and substance abuse problems, but also refers to behaviours that are not generally recognised by the medical community as problems of addiction, such as compulsive overeating.
The term addiction is also sometimes applied to compulsions that are not substance-related, such as problem gambling and computer addiction. In these kinds of common usages, the term addiction is used to describe a recurring compulsion by an individual to engage in some specific activity, despite harmful consequences to the individual's health, mental state or social life.
Prior to the latter half of the 20th Century, addiction was primarily a pharmacological term that referred to the process of developing drug tolerance so that more of a drug was required, more frequently, for the same effect to occur. However, with the founding of Alcoholics Anonymous in 1938, the allergy concept eventually morphed into the disease-model of addiction was proposed, based on the work of Dr. William Duncan Silkworth, and began to gather support in the professional community, amongst medical and social services workers, and amongst addicts themselves. The disease-model concept led to a definition of addiction based on the continued use of alcohol or drugs despite negative consequences for the user. This latter definition is now thought of as a disease state by the medical community. Morse and Flavin summarise the disease-model definition of addiction commonly utilized by treatment centers and substance abuse counselors:
Addiction is a primary, progressive, chronic disease with genetic, psychosocial, and environmental factors influencing its development and manifestations. The disease is often progressive and fatal. It is characterized by impaired control over use of the substance, preoccupation with the substance, use of the substance despite adverse consequences, and distortions in thinking.
In the latter half of the 20th Century, the twelve-step program began to be applied to a wide range of problem behaviours, many never previously identified as addictions. For example, during this process the establishment of Overeaters Anonymous in 1960 led to the identification of an associated concept of food addiction and the establishment of Sex and Love Addicts Anonymous in 1977 led to the identification of the concept of sexual addiction. However, although these terms are widely used in the recovery movement, and by commentators on that movement, neither of them are widely accepted by members of the professional communities working in the fields of addiction.
In the 21st Century, attempts have been made to model addiction using the tools of Economics, for instance, by calculating the elasticity of addictive goods and determining to what extent present income and consumption has on future consumption. The model employed and the rationale for the model may be semantically driven. Its roots may lie in the language structure itself . While consulting for the US Information Agency, US Department of State, the American psychiatrist A. James Giannini,MD, reported semantic differences associated with different treatment approaches to addiction. Countries whose language-structure implied a passive state of addiction, e.g. "dependence", utilized an activist medical model. Countries whose language implied a less passive role for the state of addiction e.g. "tossicomania", ("toxic mania" in Italian) utilized a less interventionist treatment model.
In the United States, physical dependence, abuse of, and withdrawal from drugs and other substances is outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV TR). It doesn’t use the word 'addiction' at all. It has instead a section about Substance dependence:
Terminology has become quite complicated in the field. Pharmacologists continue to speak of addiction from a physiologic standpoint (some call this a physical dependence); psychiatrists refer to the disease state as psychological dependence; most other physicians refer to the disease as addiction. The field of psychiatry is now considering, as they move from DSM-IV to DSM-V, transitioning from "substance dependence" to "addiction" as terminology for the disease state.
The medical community now makes a careful theoretical distinction between physical dependence (characterized by symptoms of withdrawal) and psychological dependence (or simply addiction). Addiction is now narrowly defined as "uncontrolled, compulsive use"; if there is no harm being suffered by, or damage done to, the patient or another party, then clinically it may be considered compulsive, but to the definition of some it is not categorized as 'addiction'. In practice, the two kinds of addiction are not always easy to distinguish. Addictions often have both physical and psychological components.
There is also a lesser known situation called pseudo-addiction. (Weissman and Haddox, 1989) A patient will exhibit drug-seeking behavior reminiscent of psychological addiction, but they tend to have genuine pain or other symptoms that have been undertreated. Unlike true psychological addiction, these behaviors tend to stop when the pain is adequately treated.
The obsolete term physical addiction is deprecated, because of its connotations. In modern pain management with opioids physical dependence is nearly universal. While opiates are essential in the treatment of acute pain, the benefit of this class of medication in chronic pain is not well proven. Clearly, there are those who would not function well without opiate treatment; on the other hand, many states are noting significant increases in non-intentional deaths related to opiate use. High-quality, long-term studies are needed to better delineate the risks and benefits of chronic opiate use.
Some substances induce physical dependence or physiological tolerance - but not addiction - for example many laxatives, which are not psychoactive; nasal decongestants, which can cause rebound congestion if used for more than a few days in a row; and some antidepressants, most notably venlafaxine, paroxetine and sertraline, as they have quite short half-lives, so stopping them abruptly causes a more rapid change in the neurotransmitter balance in the brain than many other antidepressants. Many non-addictive prescription drugs should not be suddenly stopped, so a doctor should be consulted before abruptly discontinuing them.
The speed with which a given individual becomes addicted to various substances varies with the substance, the frequency of use, the means of ingestion, the intensity of pleasure or euphoria, and the individual's genetic and psychological susceptibility. Some people may exhibit alcoholic tendencies from the moment of first intoxication, while most people can drink socially without ever becoming addicted. Opioid dependent individuals have different responses to even low doses of opioids than the majority of people, although this may be due to a variety of other factors, as opioid use heavily stimulates pleasure-inducing neurotransmitters in the brain. Nonetheless, because of these variations, in addition to the adoption and twin studies that have been well replicated, much of the medical community is satisfied that addiction is in part genetically moderated. That is, one's genetic makeup may regulate how susceptible one is to a substance and how easily one may become psychologically attached to a pleasurable routine.
Eating disorders are complicated pathological mental illnesses and thus are not the same as addictions described in this article. Eating disorders, which some argue are not addictions at all, are driven by a multitude of factors, most of which are highly different than the factors behind addictions described in this article. It has been reported, however, that patients with eating disorders can successfully be treated with the same nonpharmacological protocols used in patients with chemical addiction disorders.
It is considered possible to be both psychologically and physically dependent at the same time. Some doctors, and especially scientists in related fields, make little or no distinction between the two types of addiction, since the result, substance abuse, is the same, and in terms of scientific as opposed to magical thinking, the "psychological" dependence is entirely due to physical effects of the drug on the brain.
Psychological dependence does not have to be limited only to substances; even activities and behavioural patterns can be considered addictions, if they become uncontrollable, e.g. gambling, Internet addiction, computer addiction, sexual addiction / pornography addiction, reading, eating, self-harm, vandalism, drug addiction or work addiction.
Most countries have legislation which brings various drugs and drug-like substances under the control of licensing systems. Typically this legislation covers any or all of the opiates, amphetamines, cannabinoids, cocaine, barbiturates, hallucinogens (tryptamines, LSD, phencyclidine(PCP), psilocybin) and a variety of more modern synthetic drugs, and unlicensed production, supply or possession may be a criminal offense.
Usually, however, drug classification under such legislation is not related simply to addictiveness. The substances covered often have very different addictive properties. Some are highly prone to cause physical dependency, whilst others rarely cause any form of compulsive need whatsoever. Typically nicotine (in the form of tobacco) is regulated extremely loosely, if at all, although it is well-known as one of the most addictive substances ever discovered.
Also, although the legislation may be justifiable on moral grounds to some, it can make addiction or dependency a much more serious issue for the individual. Reliable supplies of a drug become difficult to secure as illegally produced substances may have contaminants. Withdrawal from the substances or associated contaminants can cause additional health issues and the individual becomes vulnerable to both criminal abuse and legal punishment. Criminal elements that can be involved in the profitable trade of such substances can also cause physical harm to users.
Some medical systems, including those of at least 15 states of the United States, refer to an Addiction Severity Index to assess the severity of problems related to substance use. The index assesses problems in six areas: medical, employment/support, alcohol and other drug use, legal, family/social, and psychiatric.
While addiction or dependency is related to seemingly uncontrollable urges, and arguably could have roots in genetic predispositions, treatment of dependency is conducted by a wide range of medical and allied professionals, including Addiction Medicine specialists, psychiatrists, and appropriately trained nurses, social workers, and counselors. Early treatment of acute withdrawal often includes medical detoxification, which can include doses of anxiolytics or narcotics to reduce symptoms of withdrawal. An experimental drug, ibogaine, is also proposed to treat withdrawal and craving. Alternatives to medical detoxification include acupuncture detoxification. In chronic opiate addiction, a surrogate drug such as methadone is sometimes offered as a form of opiate replacement therapy. But treatment approaches universal focus on the individual's ultimate choice to pursue an alternate course of action.
Therapists often classify patients with chemical dependencies as either interested or not interested in changing. Treatments usually involve planning for specific ways to avoid the addictive stimulus, and therapeutic interventions intended to help a client learn healthier ways to find satisfaction. Clinical leaders in recent years have attempted to tailor intervention approaches to specific influences that affect addictive behavior, using therapeutic interviews in an effort to discover factors that led a person to embrace unhealthy, addictive sources of pleasure or relief from pain.
|Treatment Modality Matrix|
|Low self-esteem, anxiety, verbal hostility||Relationship therapy, client centered approach||Increase self esteem, reduce hostility and anxiety|
|Defective personal constructs, ignorance of interpersonal means||Cognitive restructuring including directive and group therapies||Insight|
|Focal anxiety such as fear of crowds||Desensitization||Change response to same cue|
|Undesirable behaviors, lacking appropriate behaviors||Aversive conditioning, operant conditioning, counter conditioning||Eliminate or replace behavior|
|Lack of information||Provide information||Have client act on information|
|Difficult social circumstances||Organizational intervention, environmental manipulation, family counseling||Remove cause of social difficulty|
|Poor social performance, rigid interpersonal behavior||Sensitivity training, communication training, group therapy||Increase interpersonal repertoire, desensitization to group functioning|
|Grossly bizarre behavior||Medical referral||Protect from society, prepare for further treatment|
|Adapted from: Essentials of Clinical Dependency Counseling, Aspen Publishers|
From the applied behavior analysis literature and the behavioral psychology literature several evidenced based intervention programs have emerged (1) behavioral maritial therapy (2) community reinforcement approach (3) cue exposure therapy and (4) contingency management strategies. In addition, the same author suggest that Social skills training adjunctive to inpatient treatment of alcohol dependence is probably efficacious.
The development of addiction is thought to involve a simultaneous process of 1) increased focus on and engagement in a particular behavior and 2) the attenuation or "shutting down" of other behaviors. For example, under certain experimental circumstances such as social deprivation and boredom, animals allowed the unlimited ability to self-administer certain psychoactive drugs will show such a strong preference that they will forgo food, sleep, and sex for continued access. The neuro-anatomical correlate of this is that the brain regions involved in driving goal-directed behavior grow increasingly selective for particular motivating stimuli and rewards, to the point that the brain regions involved in the inhibition of behavior can no longer effectively send "stop" signals. A good analogy is to imagine flooring the gas pedal in a car with very bad brakes. In this case, the limbic system is thought to be the major "driving force" and the orbitofrontal cortex is the substrate of the top-down inhibition.
A specific portion of the limbic circuit known as the mesolimbic dopaminergic system is hypothesized to play an important role in translation of motivation to motor behavior- and reward-related learning in particular. It is typically defined as the ventral tegmental area (VTA), the nucleus accumbens, and the bundle of dopamine-containing fibers that are connecting them. This system is commonly implicated in the seeking out and consumption of rewarding stimuli or events, such as sweet-tasting foods or sexual interaction. However, its importance to addiction research goes beyond its role in "natural" motivation: while the specific site or mechanism of action may differ, all known drugs of abuse have the common effect in that they elevate the level of dopamine in the nucleus accumbens. This may happen directly, such as through blockade of the dopamine re-uptake mechanism (see cocaine). It may also happen indirectly, such as through stimulation of the dopamine-containing neurons of the VTA that synapse onto neurons in the accumbens (see opiates). The euphoric effects of drugs of abuse are thought to be a direct result of the acute increase in accumbal dopamine.
The human body has a natural tendency to maintain homeostasis, and the central nervous system is no exception. Chronic elevation of dopamine will result in a decrease in the number of dopamine receptors available in a process known as downregulation. The decreased number of receptors changes the permeability of the cell membrane located post-synaptically, such that the post-synaptic neuron is less excitable- i.e.: less able to respond to chemical signaling with an electrical impulse, or action potential. It is hypothesized that this dulling of the responsiveness of the brain's reward pathways contributes to the inability to feel pleasure, known as anhedonia, often observed in addicts. The increased requirement for dopamine to maintain the same electrical activity is the basis of both physiological tolerance and withdrawal associated with addiction.
Downregulation can be classically conditioned. If a behavior consistently occurs in the same environment or contingently with a particular cue, the brain will adjust to the presence of the conditioned cues by decreasing the number of available receptors in the absence of the behavior. It is thought that many drug overdoses are not the result of a user taking a higher dose than is typical, but rather that the user is administering the same dose in a new environment.
In cases of physical dependency on depressants of the central nervous system such as opioids, barbiturates, or alcohol, the absence of the substance can lead to symptoms of severe physical discomfort. Withdrawal from alcohol or sedatives such as barbiturates or benzodiazepines (valium-family) can result in seizures and even death. By contrast, withdrawal from opioids, which can be extremely uncomfortable, is rarely if ever life-threatening. In cases of dependence and withdrawal, the body has become so dependent on high concentrations of the particular chemical that it has stopped producing its own natural versions (endogenous ligands) and instead produces opposing chemicals. When the addictive substance is withdrawn, the effects of the opposing chemicals can become overwhelming. For example, chronic use of sedatives (alcohol, barbiturates, or benzodiazepines) results in higher chronic levels of stimulating neurotransmitters such as glutamate. Very high levels of glutamate kill nerve cells, a phenomenon called excitatory neurotoxicity.
Szasz is not alone in questioning the standard view of addiction. Professor John Booth Davies at the University of Strathclyde has argued in his book The Myth of Addiction that 'people take drugs because they want to and because it makes sense for them to do so given the choices available' as opposed to the view that 'they are compelled to by the pharmacology of the drugs they take'. He uses an adaptation of attribution theory (what he calls the theory of functional attributions) to argue that the statement 'I am addicted to drugs' is functional, rather than veridical. Stanton Peele has put forward similar views.
Experimentally, Bruce K. Alexander used the classic experiment of Rat Park to show that 'addicted' behaviour in rats only occurred when the rats had no other options. When other options and behavioural opportunities were put in place, the rats soon showed far more complex behaviours.