Drug Misuse and Abuse The concepts of ‘drug misuse’ and ‘drug abuse’ are sometimes used interchangeably. However, according to dictionary deﬁnitions, the terms are slightly different. Proctor (1995) deﬁnes ‘misuse’ and ‘abuse’ as follows: Misuse: ‘. . . to use something in an unsuitable way or in a way that was not intended’. Abuse: ‘. . . to use or treat someone or something wrongly or badly, especially in a way that is to your own advantage’. The use of the term drug ‘misuse’ in the drugs literature tends to reﬂect these general deﬁnitions. ‘Drug misuse’ is often used to refer to inappropriate- ate use of legal drugs and ‘drug abuse’ is often used to refer to excessive use of legal drugs (‘bad use’) or any use of illegal drugs (‘wrong use’). ‘Drug misuse’ might arise, therefore, as a result of using legal drugs for reasons other than their intended purpose, such as taking laxatives to achieve weight loss. ‘Drug abuse’ might arise when legal drugs are used excessively to such an extent that they could result in harm to the user. Use of cannabis would be considered ‘drug abuse’ because, in most cases, it is an illegal drug and any use would be regarded as abuse. Hence, it would be expected that the term ‘drug abuse’ would be most common in the drugs literature. In a recent National Institute on Drug Abuse report, ‘problematic drug use’ is deﬁned as: ‘The use of a substance to modify or control mood or state of mind in a manner that is illegal or harmful to oneself or others’ (Trachtenberg and Fleming 2004: 1).