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1. INTRODUCTION

BOX 1.2

Criteria for substance dependence in ICD-10
Three or more of the following must have been experienced or exhibited together
at some time during the previous year:
1. a strong desire or sense of compulsion to take the substance;
2. difficulties in controlling substance-taking behaviour in terms of its onset,
termination, or levels of use;
3. a physiological withdrawal state when substance use has ceased or been
reduced, as evidenced by: the characteristic withdrawal syndrome for the
substance; or use of the same (or a closely related) substance with the intention
of relieving or avoiding withdrawal symptoms;
4. evidence of tolerance, such that increased doses of the psychoactive substance
are required in order to achieve effects originally produced by lower doses;
5. progressive neglect of alternative pleasures or interests because of
psychoactive substance use, increased amount of time necessary to obtain
or take the substance or to recover from its effects;
6. persisting with substance use despite clear evidence of overtly harmful
consequences, such as harm to the liver through excessive drinking, depressive
mood states consequent to heavy substance use, or drug-related impairment of
cognitive functioning. Efforts should be made to determine that the user was
actually, or could be expected to be, aware of the nature and extent of the harm.
Source: WHO, 1992.

positive on at least three of these is diagnosable as “dependent”. Some of the
criteria are measurable in biological terms, while others are not. The two criteria
most easily measured biologically are the third and fourth in Box 1.2: with-
drawal – the occurrence of unpleasant physical and psychological symptoms
when use of the substance is reduced or discontinued, and tolerance – the
idea that increased amounts of the drug are required to achieve the same effect,
or that the same amount produces less effect. The other four criteria for
dependence include elements of cognition, which are less accessible to
biological measurement, but are becoming measurable using improved
neuroimaging techniques (see Chapter 3). In the sixth criterion, for instance,
the user’s knowledge of specific causal connections is to be ascertained,
something not accessible to direct biological measurement or to an animal
model. The first criterion, “strong desire or sense of compulsion”, requires
inquiry into the user’s self-perceptions, and relates to the idea of craving for
the substance. It has proved difficult to agree on a definition of the concept of
craving, and the applicability of biological models to the concept remains
controversial (Drummond et al., 2000). The criteria for substance dependence
in the fourth edition of the Diagnostic and Statistical Manual (DSM-IV) of the

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