Dependence physiological

Verheul et al. (2004) pooled data from seven European acamprosate studies in an effort to identify patient-related predictors of response to the medication. Although they examined a number of potential predictors, including patients level of physiological dependence before treatment, family history of alcoholism, age of onset of alcoholism, baseline anxiety symptom severity, baseline craving, and gender, none was shown to interact with acamprosate treatment. These findings led the authors to conclude that, although the effect size for acamprosate was moderate, the medication can be considered potentially effective for all patients with alcohol dependence. 

Targets for toxins can be considered to exist at various levels. Toxins may evolve which subdue prey by either blocking the systems responsible for locomotion, circulation, or for central coordination, in the potential victim. In order to disable these systems, advantage is often taken of the fact that their physiology depends upon specific transmembrane channels such as those for sodium, potassium, and calcium ions. 

With Physiological Dependence evidence of tolerance or withdrawal (i.e., either item 1 or 2 is present) or Without Physiological Dependence no evidence of tolerance or withdrawal (i.e., neither item 1 nor 2 is present)... 

Though most abused drugs can cause some degree of physiologic dependence, the severity of withdrawal varies considerably among these drugs. Table 33-2 lists the common... 

Dependence. The term dependence has at least two meanings in the context of substance use. First, it can refer to physical (i.e., physiological) dependence. This is a pharmacological property of the drug and is typically a predictable consequence of repeated substance use. Physiological dependence implies either tolerance (more of the drug is required for the previously obtained effect) or the propensity for withdrawal upon discontinuation of the substance. The phenomenon of physical... 

In contrast, some drugs of abnse prodnce intense craving and are highly addictive bnt do not prodnce physical dependence. The absence of physical dependence indicates the relative lack of physiological withdrawal. This is not synonymous with meaning that discontinuation of these componnds may not be psychologically nncomfortable. Two examples are marijnana and cocaine. One need only look to the recent crack epidemic to see evidence of the way these substances can destroy lives, bnt they do not produce tolerance or risk of withdrawal to the same extent as alcohol or heroin. As a result, we would say that the daily crack or marijuana user meets the dehnition of substance dependence bnt does not exhibit true physical (or physiological) dependence. 

A second issue relating to long-term medication is the effect of withdrawing medication at the end of a period of treatment. Benzodiazepines are associated with discontinuation symptoms, and their repeated use may foster the development of true physiological dependence. In a study of discontinuation of treatment for panic disorder [Rickels et al. 1993) with either alprazolam [n = 27), imipramine [n = 11) or placebo [n = 10), a withdrawal syndrome was observed in almost all patients treated with alprazolam but in few pa-... 

This is not an unusual phenomenon. It has been observed in patients who have become psychologically dependent on an inactive placebo, as well as in patients psychologically dependent on medicines not known to cause physiological dependency and withdrawal symptoms. Another example of psychological dependency on a BZD is the patient who allays anxiety about being without a pill by carrying it at all times, comforted by the knowledge that a tablet is at hand in case of need. Such patients may become acutely anxious whenever the pill has been lost or left at home. 

Long-acting drugs such as chlordiazepoxide and diazepam and, to a lesser extent, phenobarbital are administered in progressively decreasing doses to patients during withdrawal from physiologic dependence on ethanol or other sedative-hypnotics. Parenteral lorazepam is used to suppress the symptoms of delirium tremens. 

It has generally been assumed by alcoholism treatment personnel in most industrialized countries that the disease-labeling process and the alcoholic s concomitant acceptance of the "sick" role would facilitate treatment and potentiate the chances of rehabilitation. Some writers... however, question the utility of indiscriminate application of the disease label, not only because it may not be appropriate for all varieties of alcohol-related problems, but also because it may influence the very behavior it attempts to describe. This could come about... by altering the cognitive expectancies held by alcoholics and by those in their immediate social environment, such that the drinker no longer is seen as responsible for his or her behavior. In this view, loss of control over drinking may result more from learned expectations than from physical predispositions, and chronic alcoholism more from a dependency role than from physiological dependence. 

---