Check out the courses we offer
Knowledge Base » Mental Health » How do Drugs and Alcohol Affect Mental Health?

How do Drugs and Alcohol Affect Mental Health?

Last updated on 20th December 2023

Drugs and alcohol change the way your brain and body work. All drugs and alcohol use will have some kind of effect on your mental health, as they change the balance of chemicals that help your brain to think, feel, create and make decisions. The way you see things, your mood and your behaviour can all be affected to a greater or lesser extent by the influence of drugs or alcohol.

It can be tempting to use drugs or alcohol as an escape or coping mechanism when things in life are difficult, however, these are addictive substances that can cause symptoms of depression and/or anxiety or make an existing problem worse. There is often an overlap between mental health disorders such as mood, anxiety, depression or schizophrenia and the misuse of alcohol or drugs.

The subject of alcohol, drugs and mental health is complex. Some people may be more at risk to experiencing negative mental health effects than others. What causes a positive effect for one person may cause a negative effect for another.

Even when the same person takes the same drug (including alcohol) on different occasions, the effects can be different. Chronic use of some drugs (including alcohol) can lead to both short- and long-term changes in the brain, which can lead to mental health issues including paranoia, depression, anxiety, aggression, hallucinations, and other problems. Even if you have previously had no mental health problems, you may still develop symptoms of a mental health problem from using drugs and/or alcohol.

What Makes a Person Using Drugs and/or Alcohol ‘At Risk’ to Negative Mental Health Outcomes?

  • Starting to use drugs and/or alcohol at a young age.
  • If they have already been diagnosed with or are experiencing mental health issues.
  • Using stronger drugs and/or alcohol and using more frequently.
  • Having a family history of mental illness increases the likelihood of experiencing negative mental health effects when using substances regularly.

How you react to a substance at a particular point in time can depend on the type of drug and its contents/potency, your starting point regarding how you are feeling, and the condition of your mental health as well as the setting you are in.

Alcohol and other drugs can have very unpredictable effects on mood and also make people more impulsive. This can cause some people to feel suicidal in the short or the long term. The effects of some drugs could make existing feelings or conditions even worse.

Young Women Worsening Her Mental Health With Taking Drugs And Drinking Alcohol


According to the Mental Health Foundation 16.6% of adults in England report drinking to hazardous levels, while 1.2% report levels which indicate probable dependence on alcohol. 3.1% of adults in England show signs of drug dependence and men (4.3%) are more likely to be dependent on illegal drugs than women (1.9%).

Adults with drug dependence are twice as likely as the general population to be using psychological therapy and half of people with drug dependence are receiving mental health treatment.

UK Government statistics show that there are an estimated 589,000 people who are dependent on alcohol in England and about a quarter of them are likely to be receiving mental health medication; mostly for anxiety and depression, but also for sleep problems, psychosis and bipolar disorder. NHS statistics show that there were 7,545 hospital admissions with a primary diagnosis of drug-related mental health and behavioural disorders.

A survey by the Priory Group in the UK identified that a third of individuals who are at risk of alcohol and drug use disorders also use mental health services, and those with more severe mental health disorders have been found to be more likely to smoke and misuse alcohol and other recreational drugs.

Mental Health and Recreational Drugs Including Alcohol

Recreational drugs are substances that fall into two main categories – legal and illegal. In the UK the legal substances are:


Nicotine (usually in the form of tobacco, but also vaping). Nicotine is a stimulant drug and whilst there are not normally mental health effects from using nicotine, it is extremely addictive.

Nicotine use is an addiction that is made up of three parts: chemical addiction, habits and emotional ties. It affects the chemicals in your brain and you may feel good for a moment or two after lighting up.

After you’ve been smoking for a while, your body gets used to nicotine and relies on it to feel normal.

Giving up nicotine can cause withdrawal symptoms and negative mental health effects such as:

  • Irritability.
  • Restlessness.
  • Depression.

This is because your body is withdrawing from a chemical addiction. Smoking cessation programmes may prescribe medication such as bupropion (Zyban), varenicline (Champix) or a benzodiazepine to help cope with the withdrawal effects and reduce dependency.

For advice and support to quit nicotine see:


Alcohol, although legal, is the most toxic of the commonly used drugs. Moderate drinking is not usually a problem, although even moderate drinking can have negative effects over a long period of time.

Alcohol is a depressant drug which means that initially you may feel relaxed and more sociable, which can make you drink more in order to recreate or extend the pleasant effects. As you drink larger amounts you may exhibit uninhibited behaviour or aggression as the alcohol affects your mood and your behaviour.

Longer-term mental effects of alcohol misuse can include:

  • Memory loss.
  • Difficulty thinking clearly.
  • Difficulty problem-solving.
  • Poor concentration.
  • Addiction.
  • Anxiety.
  • Delirium (confusion, disorientation, hallucinations).

Most people use alcohol to relieve anxiety and to relax. Alcohol provides this outcome by increasing the effects of Gamma-aminobutyric acid (GABA), a neurotransmitter responsible for creating feelings of calm and euphoria. It also decreases glutamate, another neurotransmitter that creates excitability.

Heavy drinking makes it harder and harder to increase GABA and decrease glutamate, so more and more alcohol is required for the same outcome. Your body becomes accustomed to these changes and responds by producing more glutamate and less GABA.

Giving up alcohol is not really a problem for the “social drinker”, however, for people with an alcohol dependency, it can be dangerous to stop drinking suddenly. When you suddenly stop drinking, you are no longer impacting these two neurotransmitters, but your body is still overproducing glutamate and underproducing GABA.

As a result, you may experience both physical and mental withdrawal symptoms such as:

  • Feeling anxious or nervous.
  • Feeling irritable.
  • Feeling depressed.
  • Feeling wiped out and tired.
  • Shakiness.
  • Mood swings.
  • Not being able to think clearly.
  • Having nightmares.
  • Dilated pupils.
  • Difficulty problem-solving.
  • Sweating.
  • Headache.
  • Difficulty sleeping.
  • Nausea and/or vomiting.
  • Appetite loss.
  • Faster heart rate.
  • Pale skin.
  • Tremor.

And more seriously, delirium tremens (the DTs) – symptoms can include:

  • Fever.
  • Extreme agitation.
  • Seizures.
  • Extreme confusion.
  • Hallucinations (feeling, seeing, or hearing things that aren’t there).
  • High blood pressure.

GPs, hospitals and detox establishments have experienced staff who are familiar with these symptoms and have the tools to provide appropriate treatment, which is why it is important to seek professional help to give up drinking. Changing alcohol habits can take time, but with support and perseverance you will notice positive changes in your mental and physical wellbeing.

For advice and support to deal with alcohol dependency see:

Alcohol And Drugs Worsening There Mental Health

In the UK, illegal substances include:


Cannabis (marijuana, hemp, hashish, grass, skunk) is a stimulant, depressant and hallucinogen drug. People take cannabis as a way of relaxing and getting high.

The effects that you experience will largely depend on:

  • Whether you are used to taking the drug.
  • How much you take.
  • The type of cannabis you use.
  • Your genes.

And may include:

  • Feeling relaxed.
  • Talkative.
  • Finding things very funny and laughing a lot.
  • Feeling excited by the things you see, hear and feel.
  • Hunger.

If you have experience of anxiety and depression, you are more likely to experience negative side effects which can include:

  • Impaired short-term memory.
  • Impaired attention, judgement, and other cognitive functions.
  • Impaired coordination and balance.
  • Increased heart rate.
  • Anxiety, paranoia.
  • Psychosis (uncommon).
  • Impaired learning and coordination.
  • Sleep problems.

And with longer-term use:

  • Potential for marijuana addiction.
  • Impairments in learning and memory with potential loss of IQ.
  • Increased risk of chronic cough, bronchitis.
  • Increased risk of other drug and alcohol use disorders.
  • Increased risk of schizophrenia in people with genetic vulnerability.

Cannabis can cause depression, acute panic attacks or ongoing anxiety and paranoia, even in people who have never previously shown signs of having a mental health condition. There is no known ‘safe’ level of cannabis use.

For advice and support visit:


Cocaine is a stimulant drug. Cocaine comes in two forms:

  • Cocaine powder, which is snorted.
  • Crack cocaine, which is smoked.

Both forms may be injected. Cocaine is notoriously impure, and often contains other substances.

Short-term effects include:

  • Feeling wide awake.
  • Full of energy.
  • Feeling confident.

High doses may cause:

  • Hallucinations and delusions.
  • Depression.
  • Suicidal thoughts.

And long-term use may cause:

  • Depression.
  • Anxiety.
  • Panic attacks.
  • Paranoia.
  • Irreversible brain damage.
  • Worsening of pre-existing mental health problems.
  • Repetitive movements.

Some people can feel very low, anxious or depressed after using cocaine because of the chemicals they change in your body such as serotonin and dopamine. This is known as a ‘comedown’. A comedown is the process your body goes through when recovering from the effects of drugs, like a hangover is to alcohol. Cocaine is extremely addictive, and it is very difficult to stop taking it. If you have an existing mental health problem, cocaine can make this worse.


Ecstasy (MDMA) is a synthetic drug that alters mood and perception (awareness of surrounding objects and conditions). It is chemically similar to both stimulant and hallucinogen drugs, producing feelings of increased energy, pleasure, emotional warmth, and distorted sensory and time perception.

Ecstasy tablets are notoriously impure, and often contain substances other than MDMA. It is very dangerous to take Ecstasy at the same time as antidepressants.

Effects of Ecstasy use include:

  • Lowered inhibition.
  • Enhanced sensory perception.
  • Increased heart rate and blood pressure.
  • Muscle tension.
  • Nausea.
  • Faintness.
  • Chills or sweating.
  • Sharp rise in body temperature leading to kidney failure or death
  • Long-lasting confusion.
  • Depression.
  • Problems with attention, memory and sleep
  • Increased anxiety.
  • Impulsiveness.
  • Less interest in sex.

Withdrawal symptoms can include:

  • Fatigue.
  • Loss of appetite.
  • Depression.
  • Trouble concentrating.

For advice and support visit:


LSD is an abbreviation of the scientific name lysergic acid diethylamide. LSD is a hallucinogen drug manufactured from lysergic acid, which is found in ergot, a fungus that grows on rye and other grains.

It causes random and sometimes frightening effects, known as a ‘bad trip’, which may be delayed. As LSD causes you to hallucinate and lose touch with your surroundings, it can cause you to do dangerous things (such as attempting to fly, for example). In some cases, people have died due to dangerous behaviour as a result of taking LSD.

Effects of LSD use include:

  • Detachment from surroundings.
  • Altered sense of space and time.
  • Hallucinations.
  • Feelings of insight, mysticism and spirituality.
  • Feeling that you can fly.
  • Anxiety (associated with a bad trip).
  • Feeling panicky (associated with a bad trip).
  • Worsening of existing symptoms of schizophrenia.
  • Flashbacks of bad trips, when you feel you are re-living them.


Ketamine is an anaesthetic that is mainly used in animals. It has antidepressant effects and is being researched for use in treatment-resistant depression and PTSD. It is a hallucinogen drug that causes the user to feel detached from reality and is sometimes used as a date rape drug.

Effects of ketamine use include:

  • Problems with attention, learning and memory.
  • Dreamlike states, hallucinations, sedation, confusion.
  • Loss of memory.
  • Raised blood pressure.
  • Unconsciousness.
  • Dangerously slowed breathing.
Suffering From Alcohol And Drug Problem Whilst Suffering With Mental Health

Drug Types Explained

Stimulant Drugs

These make you feel:

  • Energetic.
  • Alert.
  • Talkative.
  • Active.
  • Very excited.

They can be very dangerous (causing death) at high doses. Repeated use can cause psychosis and paranoia, which may be diagnosed as schizophrenia. They are also addictive.

Depressant Drugs

These make you feel:

  • Relaxed.
  • Chilled out.
  • Mellow.
  • Possible paradoxical effects – anxiety, nightmares, aggression.

They are dangerous at high doses. They are addictive.

Hallucinogen Drugs

These vary a lot. The same drug may have different effects at different times.

These may cause:

  • Feelings of detachment from your surroundings.
  • Mood swings.
  • Altered sense of space and time.
  • Hallucinations, illusions and distortions of reality.
  • Feelings of insight.
  • Mystical or religious experiences.

The experience may be powerful and not much fun.

Getting Help

If your drug and/or alcohol use is affecting your mental health, you should seek help.

You can contact your GP, the NHS drug and alcohol service or specialist organisations such as:

If you’re taking prescribed medication for anxiety or depression, it’s also important to remember that alcohol and most illegal drugs interact with your medications and can reduce their effectiveness or increase the chance of side effects.

If you are taking antidepressants, it is important to understand how your medication might interact with drugs or alcohol. Minimising your drug or alcohol use or cutting it out completely will assist with recovery and reduce potential side effects.

If you are not already getting help with your mental health from your local mental health team, a good first step is to make an appointment to see your GP. Your GP may offer you medication and therapy to treat your mental illness.

They may refer you to a drug and alcohol service to help you with your drug use. If you have a mental illness and use drugs, the NHS may call this ‘dual diagnosis’ or ‘co-occurring diagnosis’. Your local NHS trust may have a policy that says how they will help people with dual diagnosis.

[ucaddon_uc_solid_side_carousel_content title=”Drug and Alcohol Awareness” bg_color=”#094b77″ image=”157495″ btn_text=”Take a look at this course” link=”” uc_fonts_data=”JTdCJTIyYnRuX3RleHQlMjIlM0ElN0IlMjJjdXN0b20lMjIlM0ElMjJ0ZXh0LXRyYW5zZm9ybSUzQSUyMG5vbmUlM0IlMjIlN0QlN0Q=”]JTNDaDQlMjBzdHlsZSUzRCUyMmNvbG9yJTNBJTIzZmZmZmZmJTIyJTNCJTNFSnVzdCUyMCVDMiVBMzIwJTNDJTJGaDQlM0VTdHVkeSUyMG9ubGluZSUyMGFuZCUyMGdhaW4lMjBhJTIwZnVsbCUyMENQRCUyMGNlcnRpZmljYXRlJTIwcG9zdGVkJTIwb3V0JTIwdG8lMjB5b3UlMjB0aGUlMjB2ZXJ5JTIwbmV4dCUyMHdvcmtpbmclMjBkYXku[/ucaddon_uc_solid_side_carousel_content]

About the author

Megan Huziej

Megan Huziej

Megan has worked with CPD Online College since August 2020, she is in charge of content production, as well as planning, managing and delegating tasks. Megan works closely with our writers, voice artists, companies and individuals to create the most appropriate and relevant content as well as also using and managing SEO. She gained her Business Administration Level 3 qualification over the duration of being at CPD Online College as well. Outside of work Megan loves to venture to different places and eateries as well as spending quality time with friends and family.

Similar posts