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and Related Health Problems (ICD) and the Diagnostic and Statistical Manual of Mental Disorders (DSM).
In the current version, ICD-10, the tenth revision of the “standard international coding tool for diseases, injuries and related health problems” (World Health Organisation 1992a) categories of mental and behavioural disorders due to psychoactive substance use in the classification of mental and behavioural disorders are listed. Categories are distinguished in some cases by single drug and in some cases by groups of drugs and in one case by the vehicle which carries the drug (namely tobacco). Further categories of clinical conditions are specified and these are common to any of the mental and behavioural disorders that are described above. The disaggregated approach which distinguishes dependence from harmful use, intoxication and withdrawal as well as from the psychiatric conditions which are related either as cause or effect of substance use, is adopted in the classification of these clinical conditions. Dependence is described as a syndrome, defined as “A cluster of physiological, behavioural and cognitive phenomena in which the use of a substance or a class of substances takes on a much higher priority for a given individual than other behaviours that once had greater value.” Two further descriptive characteristics included in the definition are the desire (strong or overpowering) to use the substance and the rapid reinstatement of the syndrome after a period of abstinence. The diagnostic guidelines (World Health Organisation 1992b) stipulate that “a definite diagnosis of dependence should usually be made only if three or more out of seven markers of the dependence syndrome have been experienced or exhibited during the previous year” but go on to say that an essential characteristic of the dependence syndrome is that either psychoactive substance taking or a desire to take a particular substance should be present. It is recommended that the diagnosis of the dependence syndrome be further specified by current use status, five categories that include three abstinent categories, one a simple ‘currently abstinent’, another defines abstinence in a protected environment suggesting the possibility of coercion and the third describes abstinence with pharmacotherapy (naltrexone or disulfiram). A further category describes controlled dependence as being the use of a substitute psychoactive substance by prescription and the three use categories distinguish use from continuous use and from episodic use.
The seven markers of the dependence syndrome described in the ICD include tolerance and withdrawal but the guidelines nonetheless caution against diagnosing the dependence syndrome in surgical patients who are given opioid drugs for pain control and experience a withdrawal syndrome “...but have no desire to continue taking the drugs”. This again supports the idea of a hierarchy in the diagnostic criteria, where tolerance and withdrawal can only be used when the desire to use the substance or actual substance use is also present. The feature of withdrawal is described as being
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