Substance use Disorder (Addiction) is a chronic and often relapsing condition. It is frequently preceded by other problems. People with substance use disorders may be aware of their ‘problem’ but feel unable to stop even if they want to. Nevertheless, people can and do recover.

Many believe that people who become addicted to drugs lack moral principles or willpower and they could stop their drug use simply by choosing to. In reality, drug and alcohol addiction is complex. Changes in the brain lead people to have intense cravings and brain imaging studies show changes in the areas of the brain that relate to judgement, decision making, learning, memory, and behaviour control. Over time, people build up a tolerance, meaning they need larger amounts of the substance to feel the effects.

Most drugs affect the brains ‘reward circuit’, causing euphoria as well as flooding it with the chemical messenger dopamine. Our functioning reward system motivates us to repeat behaviours needed to thrive, such as eating and spending time with loved ones. Surges of dopamine in the reward circuit also cause the reinforcement of pleasurable, but unhealthy behaviours, like drug-taking, leading people to repeat the behaviour again and again. As a person continues to use drugs, the brain adapts by reducing the ability of cells in the reward circuit to respond to it. The brain changes can lead to a person taking more of the drug to achieve an effect but also in reducing their ability to enjoy things they once did, such as food or social activities.

No one factor can predict if a person will become addicted to drugs. A combination of factors influences our risk.

Addiction may cause health problems as well as problems at work, financial, legal, with relationships and social problems.