Why Does Your Personality Change When Drinking Alcohol?
Alcohol has wide-reaching effects on our brains, body, and mental health. But can it also change who we are? I’ll explore why your personality changes when drinking alcohol and what you can do about it.
Why does my personality change when drinking alcohol?
Your personality changes when drinking alcohol because alcohol impairs cognitive function, lowers inhibition, increases dopamine, and alters mood. The combination of these effects leads people to engage in behavior their sober selves might otherwise avoid, like:
- Promiscuity
- Aggression
- Rage
- Extroversion
- Risk-taking behavior
- Overconfidence
- Mood swings
People can have extreme personality shifts when drinking. It’s why your shy friend starts dancing on top of the bar after a few rounds, or your quiet coworker is talking at length about his relationship with the entire table.
Over time, heavy drinking causes personality changes that extend beyond the drink.
We’ll explore all of them, plus examine which personality traits are more susceptible to alcohol abuse.

Does alcohol harm your mental health?
Alcohol abuse and mental health are deeply interconnected. Alcohol is known to exacerbate existing mental health conditions. Long-term, chronic drinking can also lead to mental health problems.
The range of mental health issues can range in severity. We know, for example, that drinking alcohol makes anxiety worse and lowers your baseline threshold for stress in your everyday life.
We also know that inflammation caused by alcohol can negatively affect your body’s ability to regulate mood.
The insidious part of the relationship between alcohol and mental health is that people will often use alcohol to self-medicate untreated or unmanaged mental health problems, making them worse.
According to the Journal of the American Medical Association, roughly 50 percent of individuals with severe mental disorders are affected by substance abuse.
And approximately 25% of people with mental health disorders struggle with substance abuse.
Additionally, people who suffer from anxiety, depression, schizophrenia, or other personality disorders are more likely to abuse alcohol.
Can drinking cause mood swings or anger?
Yes, it can!
Alcohol can also exacerbate underlying personality disorders and increase aggression, irritability, and other negative behaviors.
Some studies have also found that heavy long-term drinkers tend to be angry or hostile more often than those who don’t drink as often or much.
Additionally, the consumption of alcohol can harm someone’s mood and make them more likely to experience feelings of anger, frustration, depression, or anxiety.
Why? When we consume alcohol, it causes changes in the levels of chemicals in our brain, such as serotonin and dopamine, that are responsible for regulating our mood.
These chemical changes can contribute to feelings of anger or irritability, especially if we already struggle with negative emotions or mental health issues.
What are the Big 5 Personality Traits?
Let’s talk about the Big Five personality traits to frame a deeper dive into this conversation.
The Big Five is a model for describing human personality. The traits are extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience. Two handy acronyms for remembering these are CANOE or OCEAN.
This model is the byproduct of several independent researchers’ work, starting with Gordon Allport in the late 1930s, who first created a list of roughly 4,500 traits that make up personality. That list got whittled down to 16 traits by Raymond Cattell in 1940. Psychologists later took Cattell’s list to create what is now known as the Big Five personality traits.
These five traits are intentionally broad and measured on a spectrum, which is why they are so helpful in capturing the full complexity of human personality.
For our purposes, we will explore how alcohol alters these traits and the impact on drinkers.
Before diving in, you might want to know where you fall across The Big Five spectrum. For that, take this Big Five personality test and then come back once you’ve got your results to see how alcohol might impact your personality.
Want a little more information on personality trait psychology? This six-minute video explainer does an excellent job:
How does alcohol change your personality?
Alcohol can significantly impact your personality – both in the short and long term.
Intuitively, we know this is true. Anyone who has gotten drunk or witnessed another person get drunk has experienced this transformation in real time.
Do you get giddy and talkative? Or sad and withdrawn? Have you seen someone become angry? A combination of several of these?
Alcohol’s ability to alter our personality stems from its effect on our brain chemistry. Here’s a brief overview of what alcohol does to your brain:
- Causes neurotransmitters to relay information slower throughout the body
- Acts upon brain pathways and neurotransmitters responsible for emotional regulation and mood
- Artificially boosts the production of dopamine (which tricks the brain into thinking it is happy)
- Shrinks brain tissue
- Impairs motor function
- Causes memory loss
- Induces mood swings
- Alters the physical structure of the brain
When you drink alcohol, there are some immediate, short-term effects on your personality. Still, for heavy or frequent drinkers, long-term impacts affect the drinker even when they aren’t actively consuming alcohol.
In addition to alcohol’s impact on your brain chemistry, it can further change your mood and personality by causing:
- Gastrointestinal problems
- Cardiovascular problems
- Metabolic dysfunction
Our physical health impacts our mental health and mood. Alcohol has far-reaching impacts on all of these.
What Science Says About Alcohol Changing Personalities
A 2018 study reported the findings of a large study that examined the impact of alcohol consumption on personality. Researchers studied 39,722 participants over five years.
At the beginning of the study, participants took a Big Five personality trait assessment to determine their personality baseline. Over five years, they measured alcohol use as defined by:
- Average alcohol consumption
- Frequency of binge-drinking
- Symptoms of alcohol use disorder
- A global indicator of risky alcohol use
After five years, they reassessed participants to measure any correlation between alcohol consumption and personality changes.
They discovered how alcohol increases and decreases certain personality traits and which baseline traits made someone likely to abuse alcohol.
Let’s dive into the results and look at how this plays out in the real world.
(add graphic with the summary of what it does to big 5 personalities)
1. Alcohol increases extroversion.
It probably comes as no surprise that alcohol increases extroversion.
Extroversion refers to our level of sociability, assertiveness, and emotional expression. People with high extroversion are outgoing and adventurous, while people with low extroversion are quiet and reserved.
When you drink, increased extroversion and decreased inhibitions can have enormous consequences. It’s why we are likelier to engage in risky behavior or think a dumb idea is quite brilliant when drunk.
This effect on our personality is also why alcohol is referred to as a social lubricant.
We learn early on that drinking can help us feel more at ease with others. Introverted or less confident young people quickly find out that drinking helps them feel sociable and magically transforms them into the life of the party.
We carry those expectations of alcohol into adulthood.
The problem is we become socially stunted. We never learn to develop our social skills. Instead, we lean on alcohol to fill in those gaps.
The result is a large swatch of adults who don’t know how to socialize without alcohol.
This is partially why so many people who quit drinking feel bored and have no social life. Many people never learn how to enjoy other people’s company without alcohol.

2. Alcohol increases neuroticism.
Neuroticism is associated with emotional instability. People who score high in neuroticism are often anxious, unhappy, and prone to negative emotions. Those who score low in neuroticism are generally calm and even-tempered.
Drinking increases your levels of neuroticism. This translates to heightened aggression and emotional volatility levels in the short term.
Related Post: The Psychology Behind Drunk Texting
What alcohol-induced neuroticism looks like:
Picture this, a drunk guy at a bar decides you’re his new best friend.
You don’t know each other, but here he is, smiling, telling you all of his business, and invading your personal space.
Why is he doing this?
Because his extroversion levels are elevated.
He is the happiest man alive and has zero inhibition about telling you his life story or putting his arm on your shoulder.
You are not drunk and also not impressed, so you ask him to give you some space.
He reacts as if you just insulted his mother. His mood and posture immediately switch into defensive mode.
“Oh, excuse me! You think you’re better than me, pal?”
Now your new best friend is ready to fight you.
This is elevated levels of neuroticism at play.
People with high levels of neuroticism are easily offended, taking everything personally. They lash out and don’t handle stress well.
When this personality shift mixes with high extroversion and assertiveness, you have the recipe for an angry, volatile drunk.

But what about after you stop drinking?
For most people, the day after drinking is spent on cringe-worthy reflection of the previous night’s behavior. However, these personality changes can become more permanent for the chronic drinker.
Heavy drinkers have higher levels of neuroticism even when they are not drinking. The more they drink, the more they become someone who is:
- Easily aggravated
- Unable to cope with stress
- Unable to receive constructive feedback
- Argumentative
- Emotionally unstable
- Unmotivated
People who drink heavily and often will start to become all of these things, even when they aren’t drinking. Their personality fundamentally changes.
High neuroticism is also associated with an increased risk for anxiety and depression. Do you know what else is associated with those risks? Alcohol.
If you are a person who is naturally prone to high levels of neuroticism, consider that a significant risk factor for alcohol abuse and proceed accordingly.
3. Alcohol decreases agreeableness.
Agreeableness is associated with being cooperative, trustworthy, and good-natured.
People with high levels of agreeableness are helpful, trusting, and empathetic. Low levels of agreeableness are associated with being critical, uncooperative, and cynical.
Alcohol changes people’s personalities by making them less agreeable.
The impact is primarily felt in the drinker’s relationship with other people. They will become someone who makes selfish choices and is incapable of living up to their obligations to loved ones.
Examples of low levels of agreeableness include:
- Neglecting children and parental responsibilities
- Missing important life events
- Breaking promises
- Letting others down
- Not pulling their weight at work
In short, low levels of agreeableness turn people into nightmarishly bad coworkers, partners, and parents.

4. Alcohol decreases conscientiousness.
This is a big one.
Conscientiousness involves impulse control and our capacity for self-discipline, competence, and thoughtfulness.
People with high levels of conscientiousness are hardworking, goal-oriented, and organized. People with low levels of conscientiousness are impulsive, careless, unmotivated, and disorganized.
Low levels of conscientiousness are associated with a higher risk for alcohol abuse disorder for what I hope are obvious reasons. Impulse control determines whether a person can have a drink or two and be done.
Conscientiousness is the most significant predictor of success among the Big Five personality traits, and it also helps explain why heavy drinkers often struggle to hold jobs or advance professionally.
Low levels of conscientiousness are associated with the following traits:
- Incompetence
- Impulsivity
- Carelessness
- Procrastination
- Lack of discipline
- Disdain for rules and order
You cannot accomplish goals or complete essential tasks with low levels of conscientiousness.
High neuroticism and low agreeableness make people incapable of personal responsibility, don’t want to work, and believe the world is out to get them.
It’s a terrible place to be in. Maybe you know someone like this.

5. Alcohol didn’t impact openness.
The 2018 study did not note any noticeable change in openness among participants.
However, an early 2015 study by the same researchers noted that openness is a factor in determining who can quit drinking.
People who scored high in conscientiousness and low in openness were associated with increased odds of moving from moderate drinking to abstinence.
Additionally, a 2020 study on personality and alcohol found that high openness in women was associated with an increased risk of alcohol abuse.
In both studies, conscientiousness is a protective factor against excessive drinking.
Can you reverse the effects of alcohol on your personality?
Whether or not you can reverse these adverse effects depends on various factors, including age, pre-existing mental health conditions, how much you drink, how often you drink, and how long you’ve drunk.
Younger people who have not been drinking heavily as long as their older counterparts have a better chance of reversing the negative impact of alcohol on their personality and returning to their baseline personality.
Older adults and people who have been drinking chronically for longer may have a more challenging time. The longer you drink, the more permanent the changes to your brain structure and chemistry.
However, we shouldn’t discount the power of neuroplasticity.
Even if some personality changes cannot be entirely reversed, they can be decreased incrementally over time.
But you have to quit drinking.
If you notice your drinking negatively impacts your personality, take it seriously.
Even if you’re older and have a long road to recovery, quitting now can halt the deterioration of your personality and mental health.
I changed. You can, too.
I experienced nearly all of these personality changes at the height of my drinking. I had elevated extroversion levels. Sometimes I was a witty humorist. Other times, I was an outright clown.
But, as often with drinking, that extroversion took many turns. I was also quick to emotionally unload on acquaintances and strangers.
My neuroticism levels? Through the roof.
I became emotionally volatile, picking unwinnable fights with family members and loved ones. Most days, I woke up with crippling hangxiety and struggled with moods that tanked quickly.
I was fragile.
People who score high on neuroticism take everything personally and are incapable of managing stress or difficult conversations. I crumbled at the faintest hint of constructive feedback at work. My body physically responded to it like an attack.
Because I worked in a high-stress environment (middle school teacher), my tank would empty after only a few hours. I couldn’t control myself or my classroom, and everyone suffered for it.
When the day finished, I practically ran to the bar or home with a six-pack of cider. That first drink was like air to me.
Admittedly, my agreeableness levels tanked as well. I flaked on people. Despite wanting to be a good friend, I honestly wasn’t.
I was so absorbed in the turbulence of my inner world that I never authentically considered other people’s feelings.
I was also highly impulsive, and not just with my drinking. I racked up debt buying things I didn’t need. I did the bare minimum at my job because I had nothing else to give.
Motivation? Gone. I abandoned a dozen side projects and could not find the motivation to do anything for a sustained period.
I’m different now.
My sober personality is much more introverted and measured. I am reliable and excel at my job while maintaining a successful side business – things that would’ve been impossible in my drinking days.
My Big Five personality traits test shows high conscientiousness, agreeableness, and openness. Unfortunately, my neuroticism levels remain high as well. I struggle with anxiety and vulnerability, though I’m miles ahead of where I was ten years ago.
If nothing else, it confirms that I have no business playing with alcohol, as my risk factors are still high.
You can change your personality in sobriety.
Understanding how alcohol changes your personality can help you navigate the recovery process when you quit.
Alcohol is a crutch that stunts our emotional development. When we stop, there is a lot to undo and relearn, and that process is complicated.
Ultimately, if you don’t like who you become when you drink or feel like alcohol has produced negative, long-term changes in your personality, you have the power to change that.
That beautiful process starts when you quit.