You don’t have to go back too far to find a time when substance misuse and destructive behaviour patterns were seen purely as a matter of choice. People who developed a drug or alcohol addiction were generally seen as weak-willed or degenerate.

Now with advances in medical science we are able to observe the actual physical effects that prolonged substance misuse can have on the brain. There are still some disagreements over the precise nature of addiction, but it is widely acknowledged that it is a serious problem that is difficult to overcome without the right treatment such as that offered at a rehabilitation centre.


Modern definitions of Addiction

There are a number of different definitions or models of addiction but most working in the field of addiction and addiction recovery now consider it to be disease or disorder.

The National Institute on Drug Abuse (NIDA) defines addiction as a “chronic, relapsing disorder characterized by compulsive drug seeking and use despite adverse consequences.” It adds that addiction is considered to be a brain disorder because it “involves functional changes to brain circuits involved in reward, stress, and self-control”.

Writing in Scientific American Nora D. Volkow, the director of NIDA, said that the scientific consensus viewing addiction as a chronic but treatable condition has helped researchers to identify neurobiological abnormalities that can be targeted with therapeutic intervention, whether in a drug rehab or other setting. It is also helping to improve the way addiction is treated in a medical setting and to reduce the stigma surrounding addiction.


The effects of Addiction on the brain

When you use drugs or alcohol it affects the way that your brain functions. This results in short-term effects (such as feeling drunk or high) but prolonged use can also have a more long-term impact, essentially rewiring the brain and the way it processes the ‘reward chemical’ dopamine.

Studies have also shown that the actual structure of the brain can change over time during the course of a drug addiction. The volume of the frontal cortex can change for example, and this is the part of the brain associated with logical thinking, goal setting, planning, and self-control.

The practical impact of all this is that whether you have a heroin addiction, a prescription drug addiction, an alcohol addiction or any other kind of substance addiction, you will experience a compulsion to continue using that substance.

This compulsion will apply even when you know there may be negative consequences and can be incredibly difficult to resist without the evidence-based treatment provided in a drug or alcohol rehab.


Physical and Psychological Addictions

The fact that addiction and prolonged substance misuse has a physical effect on your brain, it may also has other potential consequences. The brain becomes used to the flood of dopamine and can build up tolerance over time. This means you need more and more of the substance to get the same feeling. Eventually you may need to drink or take drugs just to feel normal. If you suddenly withdraw the substance – by going through alcohol detox for example – you will suffer a range of physical and psychological withdrawal symptoms.

This is a physical element of addiction but there is also a strong psychological element. One study, for example, found that people with a heroin addiction experienced strong cravings when simply shown images of paraphernalia related to their drug taking. They even felt physical reactions such as racing hearts and increased blood pressure. This is an example of a psychological reaction to a physical addiction.

Some addictions such as cocaine addiction are associated primarily with psychological rather than physical addictions. There are also numerous behavioural addictions. The World Health Organisation (WHO) caused a bit of a stir when it included gaming addiction in the 2018 update of its International Classification of Diseases (ICD) but the idea of compulsive, destructive behaviour such as that associated with a gambling addiction is more well established.


Going through Detox and withdrawal symptoms

The withdrawal symptoms associated with the detoxification process represent a major barrier to recovering from addiction. These can vary widely depending on the type of substance and addiction required – the experience of someone recovering from cannabis addiction can be very different to someone coming off opioids.

Other factors such as length and heaviness of use can also have an impact but some relatively common withdrawal symptoms could include:

  • Palpitations
  • Sweating
  • Muscle cramps
  • Hallucinations
  • Headaches
  • Nausea
  • Anxiety
  • Insomnia
  • Paranoia
  • Mood swings

Cravings and some withdrawal symptoms, particularly psychological ones, can linger for a long time, which is why aftercare can be a very important part of any treatment programme.


Dual Diagnosis

There is a complex relationship between addiction and mental health. The NHS reports that somewhere between a third and a half of people who access mental health services will have co-existing mental health and substance misuse problems at some point in their lives.

In some cases substance misuse can trigger or exacerbate substance misuse and addiction while for others an addiction can trigger or exacerbate a mental health condition. It may be possible to treat both elements at the same time and this can be an important part of relapse prevention. This approach is generally known as dual diagnosis.


So is Addiction a Mental Illness?

 There is a clear link between addiction and mental illness. As noted above many people struggling with addiction will also experience distinct mental health issues and the two are often intertwined. There is also a strong psychological element to addiction but for many working in the science of addiction the fact that it has a lasting physical effect on the brain makes it more of a physical disease or disorder.

Defining addiction can be difficult and it is easy to over-simplify the complex interplay of physical and psychological factors. In the end though, the important thing to remember is that both the physical and psychological aspects of addiction can be successfully treated, leading to a full and long-lasting recovery.

John Gillen - Author - Last updated: December 14, 2021

John is one UK’s leading professionals in the addiction recovery industry. Pioneering new treatment techniques such as NAD+ and ongoing research into new therapy techniques such as systematic laser therapy, John is committed to providing the very best treatment for people throughout the UK and Europe. During his extremely busy schedule, John likes to regularly update our blog section with the latest news and trends in the industry to keep visitors to our site as well informed as possible on everything related to addiction treatment.