Understanding the Science of Alcohol Dependence and Withdrawal

Understanding the Science of Alcohol Dependence and Withdrawal

Globally, around 1.4 per cent of the population struggles with alcohol addiction. On an individual country level, this can go up to 5 per cent of a country’s population. But what causes addiction? Is it a lack of willpower? Is it inherited? Studies show that the process of developing an addiction and experiencing withdrawal is based on biology.

To understand how you become addicted to alcohol, you need to look at the science behind alcohol dependence and withdrawal. So, let’s look at it from the perspective of brain chemistry, genetics, and the neurological changes experienced during withdrawal.

What is Alcohol Dependence?

Alcohol dependence is when your body’s reward and stress systems go through major changes as a result of long-term heavy drinking. These changes result in withdrawal symptoms when you stop consuming alcohol or reduce how much you drink. The most common signs include:

  • Being unable to function without alcohol
  • Drinking, despite its negative consequences
  • Being unable to stop drinking, even when you want to
  • Consuming increasing amounts of alcohol

An alcohol home detox service offers a safe and effective way to manage these symptoms and start the path to sobriety.

What Makes Alcohol Addictive?

Alcohol is a depressant substance that, when consumed, reduces brain activity. It’s the opposite of a stimulant and works by increasing inhibitory signalling from the GABA neurotransmitter. GABA, which is responsible for communication between brain cells, can activate or inhibit certain signals. Alcohol, along with sedative drugs and muscle relaxants, increases inhibitory signalling.

GABAA, which is an inhibitory neuroreceptor that responds to the GABA neurotransmitter, controls dopamine levels in the brain. Dopamine, which creates feelings of pleasure, is released when you consume alcohol. However, prolonged alcohol abuse can cause the body to build a tolerance. As a result, your body needs a certain amount of alcohol to feel ‘normal,’ and even more to achieve the desired effect of euphoria.

Brain Chemistry and Alcohol Dependence

Typically, a normal brain rewards healthy behaviours – like exercising or spending time with your pets – with feelings of pleasure. These behaviours activate the brain’s reward pathway so you experience pleasure and are motivated to repeat them. On the other hand, your brain helps your body get out of harm’s way whenever there’s a threat of danger. And if you’re tempted to do something you shouldn’t, like spending your entire paycheck on a new wardrobe or driving over the speed limit, the frontal lobes help you determine if the benefits outweigh the consequences.

When the brain develops alcohol addiction, these brain processes are altered. Alcohol hijacks the brain’s reward pathway, causing you to want more and more to experience a similar ‘high.’ And even though alcohol can stimulate feelings of relaxation, the effect is temporary. So when the effect wears off, you end up feeling more anxious and stressed. At this point, you don’t just need alcohol for its pleasurable effects but to avoid feeling anxious.

Alcohol’s Effects on Decision-Making

One of the common questions people ask regarding alcohol addiction is, ‘Why can’t they just understand that alcohol is bad for them?’ The answer lies in how long-term alcohol abuse impacts the brain’s decision-making centre. Located at the front of the brain, the prefrontal cortex allows us to practice higher-level cognitive functions like informed decision-making. This means alcohol compromises the very area of the brain that allows you to recognize the negative effects of alcohol.

According to brain imaging studies, people with alcohol addiction experience reduced activity in the frontal cortex. And when your frontal cortex isn’t functioning properly, you can’t make the decision to stop taking alcohol, even when you realize that it’s harmful.

Brain Chemistry and Alcohol Dependence

Genetics and Alcohol Dependence

This begs the question: why do some people become addicted to alcohol while others don’t? As of yet, scientists don’t have a clear answer, but it involves a combination of factors such as genetics and heritability. Research indicates that genetics are responsible for 50 per cent of the risk of developing alcohol dependence. But it doesn’t depend on genetics alone: your environment and gene-environment interactions also affect your vulnerability to developing alcohol addiction.

What is Alcohol Withdrawal?

You experience alcohol withdrawal when you suddenly stop taking it after a prolonged period of heavy drinking. Common symptoms include irritability, agitation, anxiety, and nausea, but it also includes severe manifestations such as seizures and hallucinations.

Should you decide that the time is right to participate in a safe alcohol detox, you have the option to meet with a GP or to receive at-home detox apart from inpatient services. Let’s look at the services provided for alcohol detox.

Why The Body Experiences Alcohol Withdrawal?

Why The Body Experiences Alcohol Withdrawal?

Withdrawal symptoms occur as a result of alcohol-induced changes in your brain chemistry. These imbalances lead to excessive neuronal activity when you stop taking alcohol. Under normal conditions, the brain maintains a strict balance of excitatory and inhibitory neurotransmitters, which are glutamate and GABA, respectively.

With regular alcohol consumption, GABA receptors become less responsive to the neurotransmitter, requiring high alcohol concentrations to achieve the same effect. Now, the system has adapted to having high concentrations of alcohol, something we refer to as ‘tolerance.’ When you remove alcohol from this system, GABA receptors are less responsive, which causes an imbalance of the excitatory neurotransmitter’s effects. It’s why you feel agitated, become jittery, and, in severe cases, experience seizures.

Stages of Alcohol Addiction

There’s evidence to support that alcohol dependence develops over the course of three stages. These are the binge (intoxication), withdrawal (negative affect), and preoccupation (anticipation) stages. Each stage feeds into the next, and as you continue taking alcohol, it becomes more severe. This causes lasting changes in brain functions that impair your ability to control substance abuse.


In this stage, you experience the pleasurable effects of alcohol that reinforce consumption. As you repeatedly consume alcohol, you form a habit which leads to powerful urges and compulsive drinking.


When you stop taking alcohol, you no longer experience its positive effects. It also leads to increased activation of your brain’s stress systems. At this stage, you drink alcohol to escape the ‘low’ feelings of withdrawal.


This is when you display alcohol-seeking behaviour after a period of abstinence. You become preoccupied with thoughts of your next drink and how you can get more alcohol.


Author / Jason Shiers / Dip.Psych MBACP

Jason Shiers is a Certified Transformative Coach & Certified Psychotherapist who is a specialist in addiction, trauma and eating disorders. He has been working in the field of addiction for 25 years now.

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