The variety of different body matrices that can be analyzed to determine the presence or absence of different psychoactive substances is extensive, ranging from semen to cerumen. There are, however, practical limitations to the extent to which different biological samples can be used, and the mechanism of collection and supervision of samples are critical to the procedure. This focuses on those biological samples that are commonly used for testing within various drug treatment settings, namely, urine, saliva, blood, and hair. Urinalysis is routinely used in hospitalbased services, blood in forensic environments, hair analysis for medicolegal cases, and saliva tests have been used in the prison services and outreach units. Many would advocate that the assessment of psychoactive drug use could reliably be achieved using self-report from the drug user (client). However,the drug rehabilitation are issues around the method of inquiry the context, purpose, interviewer characteristics, etc. that may bias self-report. Circumstances where the drug user sees the self-report to the inquirer about drug use as influential on his own continued treatment or possible loss of privileges are particular examples.
With a focus on alcohol rehab, Allan has recommended that patients presenting with anxiety and alcohol dependence should first be detoxified and reassessed after 6 weeks when only an expected 10% will be found to have persistent symptoms amounting to an anxiety state. The persistent anxiety can then be treated using conventional pharmacological or behavioral methods. She points out that patients may resist such an approach, preferring to deal with their psychological distress before tackling their substance use. People who are dependent on alcohol or other drugs usually succumb to a number of financial, family, health, and relationship problems, and it is not surprising that many will complain of depression; again it is not surprising that 80% or more will recover within a few weeks of abstinence without recourse to antidepressant treatment.
With a focus on alcohol rehab, Allan has recommended that patients presenting with anxiety and alcohol dependence should first be detoxified and reassessed after 6 weeks when only an expected 10% will be found to have persistent symptoms amounting to an anxiety state. The persistent anxiety can then be treated using conventional pharmacological or behavioral methods. She points out that patients may resist such an approach, preferring to deal with their psychological distress before tackling their substance use. People who are dependent on alcohol or other drugs usually succumb to a number of financial, family, health, and relationship problems, and it is not surprising that many will complain of depression; again it is not surprising that 80% or more will recover within a few weeks of abstinence without recourse to antidepressant treatment.
The drug being tested for and the period of time that the clinician wishes to consider influence
the choice of body fluid. Blood and, to a lesser degree, saliva are likely to give the most accurate
measurement of drugs currently active in the system, whereas urine provides a somewhat broader time period, but with less quantitative accuracy. Hair provides a substantially longer time frame. The routine drug testing strategy most widely adopted is to send urine samples to a laboratory for an initial screen to detect psychoactive drugs of interest. Analysis is performed using a semiautomated commercially available immunoassay or thin layer chromatography (TOXILAB) test. Several types of the former test exist and include radioimmunoassay, RIA:Europ/DPC, enzymemediated immunoassay test, Syva:EMIT, and fluorescence polarization immunoassay, FPIA. Recently, several rapid detection devices (near patient test, NPT) for drugs of abuse screening have been marketed in the U.K. Such tests offer a more rapid turnaround of results to aid clinical decision making.
However, all initial drug screen tests are nonspecific and identify only in a nonquantitative fashion the class of drug present, e.g., opiates, amphetamines, or benzodiazepines, etc. Ideally, any positive test result should then be confirmed by a second test working on different physicochemical principles to the screening test. Gas and liquid chromatography with mass spectrometric detection are regarded as the “gold standard” and are favored where legally defensible results are required. It cannot be overemphasized that the confirmation of drug screening test results is essential. For amphetamine-specific immunoassays, the confirmation test provides the opportunity to differentiate legitimate medicines. For instance, pseudoephedrine and phentermine give a positive test result (cross-react) with tests for illicit drugs like amphetamine and methylenedioxymethamphetamine, MDMA. For opiate drugs, initial immunoassay tests for morphine crossreact with codeine, dihydrocodeine, pholcodeine, 6-monoactetylmorphine (6-MAM), morphine glucuronide, and morphine-6-glucuronide. Consequently, if more than one of these substances is present in a urine sample, the test result will relate to the concentration of the sum of all these opiates and their metabolites. In this way an inaccurate picture of the window-of-detection of opiate drugs in urine may be concluded. The clinical benefit of the confirmation test is that it is able to verify the specific substance(s) present. For example, a confirmation test can detect the presence of 6-MAM, the only specific indicator (metabolite) of heroin use .
the choice of body fluid. Blood and, to a lesser degree, saliva are likely to give the most accurate
measurement of drugs currently active in the system, whereas urine provides a somewhat broader time period, but with less quantitative accuracy. Hair provides a substantially longer time frame. The routine drug testing strategy most widely adopted is to send urine samples to a laboratory for an initial screen to detect psychoactive drugs of interest. Analysis is performed using a semiautomated commercially available immunoassay or thin layer chromatography (TOXILAB) test. Several types of the former test exist and include radioimmunoassay, RIA:Europ/DPC, enzymemediated immunoassay test, Syva:EMIT, and fluorescence polarization immunoassay, FPIA. Recently, several rapid detection devices (near patient test, NPT) for drugs of abuse screening have been marketed in the U.K. Such tests offer a more rapid turnaround of results to aid clinical decision making.
However, all initial drug screen tests are nonspecific and identify only in a nonquantitative fashion the class of drug present, e.g., opiates, amphetamines, or benzodiazepines, etc. Ideally, any positive test result should then be confirmed by a second test working on different physicochemical principles to the screening test. Gas and liquid chromatography with mass spectrometric detection are regarded as the “gold standard” and are favored where legally defensible results are required. It cannot be overemphasized that the confirmation of drug screening test results is essential. For amphetamine-specific immunoassays, the confirmation test provides the opportunity to differentiate legitimate medicines. For instance, pseudoephedrine and phentermine give a positive test result (cross-react) with tests for illicit drugs like amphetamine and methylenedioxymethamphetamine, MDMA. For opiate drugs, initial immunoassay tests for morphine crossreact with codeine, dihydrocodeine, pholcodeine, 6-monoactetylmorphine (6-MAM), morphine glucuronide, and morphine-6-glucuronide. Consequently, if more than one of these substances is present in a urine sample, the test result will relate to the concentration of the sum of all these opiates and their metabolites. In this way an inaccurate picture of the window-of-detection of opiate drugs in urine may be concluded. The clinical benefit of the confirmation test is that it is able to verify the specific substance(s) present. For example, a confirmation test can detect the presence of 6-MAM, the only specific indicator (metabolite) of heroin use .
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