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The effects of addiction on the brain can be devastating to you, your family, or your friends. 

Whether it is an addiction to alcohol or another substance, understanding how addiction and the brain affect both the physical and mental well-being of a user and their family. 

In this post, we’re going to review how drug addiction affects the brain, what causes addiction in the brain to persist, the link between alcohol addiction and the brain, and how prevention and treatment can heal the drug addict brain. 

Effects of Addiction on the Brain

Before we discuss the effects of drug addiction on the brain, it’s important to get an understanding of how the brain of a drug addict should function.

The brain is an incredibly complex organ. It makes you who you are, and it helps you get things done. Think of it as a supercomputer with a ton of pathways that help your brain communicate with the rest of your body.  Just like a computer, your brain has circuits too. These are made up of neurons, and there are billions of them in your body.

Neurons act like a switch to control how information flows from the brain to the rest of your body.

When a neuron receives enough information or signals from other neurons it is connected to, it also “fires”, or sends its own signal to other neurons in the circuit. The diagram below shows how this process works:

brain anatomy


These circuits are all interconnected networks and serve different functions and bundled together to make nerves, as seen in the diagram below:

brain and addiction


Those nerves are then part of larger systems including:

  1. The central nervous system, which is made up of the brain and spinal cord.
  2. The peripheral nervous system, which is made up of sensory and motor nerve cells.

In order to send a message or signal, a neuron sends a neurotransmitter into the gap between it and the next neuron (called a synapse) that then crosses over to the next neuron and attaches itself to its receptors. This creates a change in the postsynaptic cell. That change could trigger things like a muscle to contract or your body to begin sweating — it just depends on which neurotransmitter fires as they all have different effects.

Neurotransmitters can be classified into two main groups

  1. Small molecule neurotransmitters. 
  2. Neuropeptides.

These serve different roles in the body, which are outlined in the table below.

Neurotransmitter Function in the Body
Serotonin Regulates sleep, temperature, and mood.
Adrenaline Responsible for the “fight or flight” response in the body.
Acetylcholine Controls muscle contractions & movement.
Dopamine Known as the “Feel Good” neurotransmitter because it stimulates the neurons in the pleasure center of the brain and also helps regulate movement.
γ-aminobutyric Acid (GABA) Creates balance needed for proper brain function by inhibiting counterproductive or unnecessary neurons. 
Endorphins Helps control pain perception by inhibiting signals from pain “sensors”. 

How Does the Brain of a Drug Addict Work?

brain of a drug addict

Now we know that neurons are part of the larger nervous systems and use neurotransmitters to send messages to other neurons — but do things always go as planned? 

Not when substances are involved. 

At a cellular level, drugs interfere with how messages are sent, received, or interpreted by the neurotransmitters. When an addictive drug is used, surges of dopamine are released. That is where feelings of euphoria or intense pleasure are created in the first encounter with a substance. This is often what leads people to come back to a substance again and again — to chase that initial “high” or good feeling.

The table below lists common types, or categories, that drugs can fall into as well as the short and long-term effects of drug addiction on the brain.

Type of Drug Effect of Drug on the Brain (Short Term) Effect of Drug on the Brain (Long Term) Common Forms
Stimulant Alertness, increased focus, higher heart rate, and blood pressure, loss of appetite, and sleeplessness. Paranoia, extreme weight loss/gain, long-term insomnia. Cocaine, Caffeine, Methamphetamines, Prescription Stimulants like Dextroamphetamine-Amphetamine.  
Depressant Drowsiness, sluggish behavior, slowing of typical brain function. Effects fade over time with building tolerance causing painful, nauseating withdrawal. Seizures and death are also possible. Alcohol
Opioid Indifference to physical and emotional pain, drowsiness, slowed breathing, constipation, and death. Effects fade over time with building tolerance causing users to seek increased amounts or long, painful withdrawals.  Heroin, Fentanyl, Prescription opioids like oxycodone or hydrocodone. 


How Drug Addiction Affects the Brain

Drug addiction affects the brain in many ways. From creating lasting damage to changing habits entirely, it has long-term consequences.

Primarily, however, drug addiction affects the brain in three areas:

  1. Basal Ganglia: The part of the brain that motivates us, and helps us form habits from learning.
  2. Extended Amygdala: Involved in reward cognition, this part of the brain houses our stress systems.
  3. Prefrontal Cortex: This is the part of your brain responsible for your decision-making, thinking, and action control. 

The image below shows where those three important areas are located in the brain:

brain anatomy


Each part of the brain just listed is related to the three-stage cycle of addiction. This is a cycle that often traps users in their addiction.

The three stages of the cycle of addiction are:

  1. Binge and intoxication.
  2. Withdrawal and negative effects.
  3. Preoccupation and anticipation.

So to understand how those key parts of the brain are affected by the three-stage cycle of addiction, we have outlined their interconnections in the table below:

Stage Part of the Brain Affected By Drug Use at this Stage Stage Effects of Addiction on the Brain
  1. Binge and intoxication
Basal Ganglia People begin to experience the rush of dopamine and euphoria associated with taking the drug. 
  1. Withdrawal and negative affect
Extended Amygdala When the substance is no longer present in the user’s system, signs of physical discomfort, anxiety, or distress begin to appear.
  1. Preoccupation and anticipation
Prefrontal Cortex To alleviate the negative withdrawal feelings, a user goes back to binge and intoxication after not for a period of time. Each time, build up a tolerance as they battle for the same feeling of initial euphoria.


What Causes Addiction in the Brain to Persist?

addiction and the brain

Stopping isn’t as easy as snapping your fingers when it comes to the brain and addiction. It may have only taken a single cycle of the three-stage process to become addicted to a substance. 

The thing is, healthy adults are typically able to take control of impulses. For example, we may have an impulse to eat an ice cream sundae instead of dinner, but thanks to the judgment and decision-making circuits in our prefrontal cortex, we are able to balance those impulses. 

When it comes to the drug addict brain that is not the case. 

Prolonged drug use means those circuits that balance the impulse to use a substance don’t work as they should. Because of that, there is a reduced ability to control the strong impulses to use a substance even though the addict may be aware of the negative consequences of long-term use. 

This impairment can progress with the misuse of substances and is called a neuroadaptation. Neuroadaptations are structural and functional changes in the brain that occur as a result of long-term exposure to substances. They can drive the transition from controlled, recreational use into addiction territory as the inability to control impulses continues to wear down.

There are also things that predispose people to become more likely to use substances in the first place, then misuse them and become addicts.

Risk factors for drug addiction include two groups of factors:

  • Early life experiences: Stressors in childhood, such as abuse, neglect, poverty, and household instability can interact with the same stress circuits in the brain as addictive substances. This is thought to be why there is an increased addiction risk for these individuals. Plus, those who start using a substance during their youth are more likely to become addicted. 
  • Genetic predisposition: Between 40 and 70% of individual levels of risk for addiction can be determined by genetic characteristics. This means that some people are just born more likely than others to become addicted.

When these factors are combined, it can make for a difficult battle against addiction. 

Understand the Link Between Alcohol Addiction and the Brain

When it comes to alcohol addiction and the brain, there’s definitely a lot to understand about how this substance can negatively impact not only the brain but your overall health.

Just like with other substances, neurotransmitters (endorphins this time) are responsible for those positive feelings we get when alcohol is consumed. In the short term, alcohol use leads to impaired motor skills, judgment, and memory. With long-term use, brain damage will occur. Several studies have shown that the more alcohol consumed, the more the hippocampus — that is the part that helps with memory and reasoning — shrinks in size. 

Other long term effects of alcohol addiction and the brain that are related to the brain damage caused by alcohol abuse include:

  • Dementia
  • Deficits in learning and memory
  • Wernicke-Korsakoff Syndrome
  • Other mental disorders

Addiction and the Brain: Symptoms

addiction symptoms

Every substance may uniquely impact the brain of a drug addict and those impacts depend on many factors such as length of use, type of substance, and the user’s life experiences. 

Signs that someone you love may have a substance use disorder include:

  • Sudden money troubles, including requests to borrow money with poor explanations or even cash or items that could be sold, are missing from your home or theirs. 
  • Having problems at school or work, such as frequent or unexplained absences and drops in performance. 
  • Affected physical appearance, such as extreme weight loss or gain, lack of energy, and other physical side effects like hair loss or red eyes.
  • Change in attitude and normal behaviour, including increased irritability and cagey behaviour about whereabouts or specific areas in their home. 
  • Neglected grooming and appearance maintenance compared to their normal standards.

Over time, addiction and the brain can create more problems, like homelessness, disease, lack of family contact, and even, ultimately, death. Watching for these key signs and symptoms of addiction can help lead to the earlier intervention of substance abuse disorders. 

Addiction and the Brain: Prevention 

As discussed earlier, there are certain factors, like previous life experience and even genetics that impact the propensity for addiction. 

That being said, there are some ways to prevent addiction from taking hold, and reduce harm for those who are already becoming or are addicted. 

The chart below shows the intersection of prevention and harm reduction efforts.



The first step in prevention for those who have not used is preventing or delaying the use of a substance initially. This can be through direct educational prevention programs or ensuring protective factors like a positive adult role model in adolescence and positive peer group norms exist.

On a secondary level, early detection and intervention are needed to help further prevent addiction from taking hold. 

Finally, the tertiary option for prevention lies in harm reduction. Harm reduction for the drug addict brain can look like guidance to safer methods of taking the substance, clean paraphernalia, and ensuring basic needs like food, shelter, and safety are met. 

Addiction Treatment Options 

There is a myriad of solutions to help make sure your loved one is able to recover and help heal the brain of a drug addict. 

In this section, we will review those options. 

Drug & Alcohol Intervention Services

When it comes to drug addiction and the brain, ensuring the right team is in place is paramount. 

Andy Bhatti’s Drug and Alcohol Intervention Services give you the addiction counselling and support your family deserves. Andy focuses on making a fully customizable plan suited to the needs of the patient and the family. He gets to the full family history and conducts a phone meeting to make sure he is the right interventionist for your loved one.

In his initial interview, Andy will ask your family questions over the phone such as

  • What is their drug addiction?
  • What are they addicted to?
  • How long have they been using for?
  • Do they have kids and, or, a spouse?
  • Is the patient at risk of losing their job over the addiction?

Then Andy flies to your family and completes the intervention as per your personalized plan. Once the patient has entered treatment, Andy will continue to work with the family as almost no addiction affects just the patient themselves. 

An intervention should be considered when a person cannot stop their addiction, whether it be drugs or alcohol, by themselves or when they need a substance or stimulant to get through the day.

Outpatient Behavioural Treatment

outpatient treatment

If your loved one is suffering from the effects of addiction on the brain, it’s important to find the right program that suits their needs.

Outpatient programs are a type of substance abuse treatment that allows patients to attend the counselling and treatment programs on the basis that they do not live on-site at the facility all of the time. 

Typical settings for this kind of treatment include substance abuse treatment centers, community clinics, hospitals, or other clinical settings. Outpatient behavioural treatment occurs on a regular interval and may include overnights or weekend stays. This can be helpful for those who have professional or personal responsibilities, as it allows them to continue attending work or participating in family life alongside their treatment. 

Inpatient or Residential Treatment

For a family feeling the difficult effects of drug addiction on the brain in their loved one, an inpatient or residential treatment may be the best option.

A residential treatment center is a more intensive form of drug rehabilitation that allows the patient to remain on-site in the care setting for 24 hours per day. Typically these drug and alcohol treatment centers offer programs that last from 21 days upwards of several months. 

The treatment modalities vary, depending on the patient and the center but typically offer group counselling, individual counselling and treatment for addiction and the brain, and even family counselling. 

For publicly funded residential treatment options, the wait times may vary and can be longer than a private inpatient option.

Private Treatment Centers and Recovery Houses for Addicts

private treatment centers

Private treatment centers can be seen as most similar to inpatient or residential treatment, however, the key difference is that they are not government-funded. 

The biggest hurdle here is that the cost can be a challenge for some families, as it is private care not covered by government coverage plans.

On the other hand, it typically allows for quicker admission and more customizable treatment options for patients with addiction on the brain. Other benefits include having higher staff-to-patient ratios, more amenities, and a wide range of therapeutic modalities.

Detox Centers

If you or your loved one has been battling addiction in the brain for a long time, you may be seeking a detox treatment option.

A detox center is a facility with monitoring support and sometimes medical assistance to allow the patient to get the substance out of their system safely and under supervision.  

Once the detox is complete, facilities will help create a discharge plan that may include counselling for you or your loved one to ensure well-being and safety is at the forefront. 


Drug and substance abuse has serious impacts — on family, friends, children, professional commitments, and most of all drug addiction affects the brain. 

It’s important to understand why you or your loved one’s drug addict brain needs the right treatment and counselling to get them on track to recovery. 

If treatment and the road to recovery is something you’re looking for, there are resources available to support you:

  • Andy Bhatti Intervention and Addiction Service offer years of expertise working with and understanding the drug addict brain that is backed by the Justice Institute of British Columbia as well as other programs in the field of Intervention Skills and Training. Unsure of how Andy Bhatti can help you? Read our testimonials to hear from past clients who have made the journey to healing the drug addict brain before. 
  • Canada Drug Rehab offers a directory that is a free resource. It makes it easy to find the right counselling, treatment, and rehab programs across the country.
  • Cedars at Cobble Hill offers a setting that allows the patient to receive individualized care and support in an inpatient setting, as well as detox services. 
  • Sunshine Coast Health Centre has offered high-quality individualized care since 1991. This private facility offers a wealth of both traditional recovery support as well as nutrition and fitness to ensure all-around well-being for the patient.