What is opioid dependence?
Opioid dependence has often been described as a brain disease with a behavioral component.* Studies of brain chemistry have led to the understanding that opioid dependence is a biological brain disease that drives drug-seeking behavioral patterns that are neurologically wired to survival.1 The physical reality of withdrawal and cravings compounds the psychosocial aspect of the disease and causes a strong need to repeat the experience. Long-term fundamental changes to the structure and function of the brain often compel people to continue to misuse opioids, despite the harm they can cause.
Opioid dependence has been described by the World Health Organization and the National Institute on Drug Abuse as a brain disease with a behavioral disorder. Long-term fundamental changes to the structure and function of the brain often compel people to continue to misuse opioids, despite the harm they can cause.
Characteristic features include drug craving and maladaptive behaviour focussed on obtaining opioids at any cost. Opioid misuse can be defined as a continuous compulsion to use opioids despite physical, psychological or social harm to the user.3 The World Health Organisation suggests that the following are required for the diagnosis of opioid dependence:4 • A strong desire or sense of compulsion to take the substance. • Difficulty in controlling use. • A physiological withdrawal state. • Tolerance. • Neglect of alternative pleasures and interests. • Persistence of use despite harm to oneself and others.