The Independent Pharmacy

Mental Health Disorders: Causes, Symptoms & Treatments of Common Mental Health Problems

Scott McDougall
Scott McDougallMPharmDirector & Registered Manager

Reviewed on 10 Jun 2022

Whether you’re experiencing mental health problems or trying to support someone living with a mental health disorder, you might be looking for information that can help.

That’s why we’ve created this mental health information page — to give you a comprehensive overview of some of the common mental health disorders out there, including the main symptoms, causes and treatments for each.

For more general information about mental health, visit our ‘What is Mental Health?’ page first.

Mental health disorders: an overview

A mental health disorder (also known as mental illness) is a health condition that involves changes in emotion, thinking or behaviour. There are many different mental health disorders, and they have different symptoms that can impact peoples’ lives in different ways.

One in four adults and one in ten children experience mental illness during their lifetime. If you haven’t, then you will know and care for someone who has.

Mental health disorders are treatable and the vast majority of individuals with mental health disorders continue to live well and function in their daily lives.

Types of mental illness

There are many different types of mental illness, mental health problems, and disorders.

Below are some of the most common mental health problems and disorders:

  • Anxiety disorders (such as generalised anxiety disorder or social anxiety disorder)
  • Panic disorder (panic attacks)
  • Bipolar disorder
  • Depression
  • Eating disorders
  • Obsessive-compulsive disorder (OCD)
  • Post-traumatic stress disorder (PTSD)
  • Psychosis
  • Schizophrenia
  • Schizoaffective disorder
  • Self-harm
  • Dissociation and dissociative identity disorder (DID)
  • Borderline personality disorder (BPD)

This is not an exhaustive mental health disorders list, but it gives you a rough idea of the huge variety of mental health problems and disorders out there.

Common mental health problems

One in four people will experience mental illness in their lifetime, and there are some mental health problems that are more common.

While people can experience mental illness or mental health problems in very different ways, most people will share common signs and symptoms which characterise and indicate a specific mental health disorder.

Learning more about these common mental health problems and their more typical symptoms might help you to feel more confident about facing a problem and getting help, whether that’s for you or someone close.

You can find out more about common disorders here, including causes of mental health, symptoms and treatments.

Anxiety and panic attacks

The term ‘anxiety’ is often used to describe feelings of unease, worry and fear.

We all experience these feelings at some point in our lives and it’s perfectly natural to do so, especially if you’re nervous about a certain situation, a big decision, or an upcoming event such as an exam or an interview. During these times, feeling anxious can be normal.

However, if you feel anxious all or most of the time, then you may have an anxiety disorder. Anxiety disorders include generalised anxiety disorder (GAD), panic disorder (where you will experience panic attacks), social anxiety disorder, and specific phobias.

What causes anxiety and panic attacks?

We don’t know exactly what causes anxiety and panic attacks, but there are some factors that may trigger or cause anxiety:

  • Research suggests that an imbalance of the brain chemicals serotonin and noradrenaline (which help to control and regulate mood) may cause anxiety, as well as overactivity in certain areas of the brain.
  • Genetics are thought to increase your chances of suffering from an anxiety disorder — if you have a close relative with the condition, you are more likely to develop it.
  • Life experiences and circumstances can also cause anxiety. Experiencing something traumatic like the loss of a loved one, illness, bullying, unhealthy relationships, abuse, violence, or a big life change such as becoming pregnant or moving house can all cause anxiety.
  • Panic attacks can also be associated with a particular place, object or situation, and some people can find the thought of having a panic attack itself a trigger.

Symptoms for anxiety and panic attacks

Anxiety can be experienced through our thoughts, feelings and physical sensations. Anxiety disorders can have many physical and psychological symptoms, and what you experience may be different from what other people experience.

However, here are some of the more common physical symptoms of anxiety:

  • Rapid breathing or difficulty breathing
  • Heart palpitations (a raised heart rate, fluttering or pounding heart)
  • Nausea and stomach-churning
  • Lightheadedness and dizziness
  • Excessive sweating
  • Trouble sleeping
  • Blurry vision
  • Loss of libido
  • Tense muscles
  • Headaches
  • Pins and needles

Here are some common psychological symptoms:

  • Feeling nervous and tense
  • Feeling overwhelmed and flooded with thoughts
  • Intrusive thoughts
  • Obsessive thoughts
  • Restlessness
  • Inability to concentrate
  • Being unable to relax
  • Having feelings of dread and fearing the worst
  • Fixating on the negative
  • Rethinking a situation over and over again
  • Feeling numb

Treatment for anxiety and panic attacks

If anxiety is affecting your daily life or causing you distress, then it’s a good idea to see your GP. They will ask you about your symptoms and your worries, fears and emotions to try to find out more.

They may suggest treatments that can help ease your symptoms. These include talking treatments such as cognitive behavioural therapy (CBT), or medication — such as beta-blockers, like Propranolol, or a type of antidepressant called selective serotonin reuptake inhibitors (SSRIs).

There are some things you can do for yourself to help with anxiety, such as breathing exercises, mindfulness and meditation, or keeping a diary. Lifestyle changes like regular exercise, getting enough sleep and maintaining a healthy, balanced diet can all help with anxiety.

Bipolar disorder

Bipolar disorder — also known as bipolar affective disorder — is a mood disorder which can cause periods or episodes of extreme low (depressed) and extreme high (manic) moods.

People who have bipolar disorder may feel well and have periods of ‘normal’ mood between episodes of mania and depression. Each extreme episode can last for several weeks, or possibly even longer.

There are different types of bipolar disorder, including Bipolar I, Bipolar II, and Cyclothymia. Bipolar disorder can only be diagnosed by a mental health professional such as a psychiatrist.

Bipolar used to be called manic depression.

What causes bipolar disorder?

The cause of bipolar disorder is not clear, but it is thought to be a combination of different genetic and environmental factors.

Here are a few possible causes of bipolar:

  • Genetic factors: you are five times more likely to develop bipolar disorder if someone in your immediate family has it.
  • Brain chemical imbalance: too much or too little of certain chemicals in your brain can affect your mood and behaviour, causing you to develop mania or depression.
  • Environmental factors: traumatic or stressful life events such as abuse or the loss of a loved one can trigger symptoms of bipolar disorder, particularly depressive episodes.

Symptoms for bipolar disorder

The symptoms of bipolar disorder depend on which mood you're experiencing — either the low (depressive) or high (manic) episodes of the disorder.

Symptoms of mania/a manic episode can include:

  • Feeling euphoric, excited, confident or adventurous
  • Feeling like you have lots of energy
  • Feeling like you are untouchable/can’t be harmed
  • Having racing thoughts and ideas
  • Making ambitious plans
  • Talking quickly
  • Difficulty concentrating/being easily distracted
  • Becoming annoyed or agitated easily
  • Increased sex drive
  • Not feeling like eating or sleeping
  • Hearing voices or seeing things that others can’t hear

Symptoms of depression/a depressive episode can include:

  • Feeling down, easily upset and teary
  • Feeling hopeless, helpless, or empty
  • Low self-esteem/lack of confidence, feelings of worthlessness
  • Feeling tired and having less energy
  • Heavy, sluggish feelings
  • Lack of motivation
  • Inability to enjoy the things that you used to or enjoying them less
  • Difficulty concentrating, remembering or making decisions
  • Feeling restless or irritable
  • Sleeping too much or difficulty sleeping
  • Losing your appetite (or an increase in appetite)
  • Loss of libido
  • Suicidal thoughts and feelings

Treatment for bipolar disorder

To be treated for bipolar disorder, you will need to be diagnosed first. You can only be diagnosed with bipolar disorder by a mental health professional, such as a psychiatrist — not by your normal GP.

However, if you think you’re experiencing bipolar moods and symptoms, then discussing this with your GP is a good first step. They will be able to guide you through the next steps, referring you to a psychiatrist who will be able to assess you.

The exact combination of treatments you’re offered will depend on whether you’re trying to manage a current bipolar episode — either depressive or manic — or are looking to manage your mental health in the long term.

If you’re currently experiencing a high or low episode, you are likely to be offered medication. Medications like mood stabilisers are used to manage mania and depressive symptoms and can be used as part of a longer-term medication plan.

You might be offered a talking therapy such as CBT or interpersonal therapy that is specially designed for you and bipolar disorder.

The aim of treatment is to help you maintain stable moods and manage your symptoms well.


Depression is one of the most common mental health problems, affecting millions of people across the world. Many of us will experience depression over the course of our lives and the likelihood that you know someone who has or has had depression is very high. A lot of people who have depression will also experience anxiety too.

We all have times when our mood is low and we're feeling sad about things in our lives. Usually, these feelings will pass. If these feelings don’t go away or are interfering with your life, then you may have depression.

Depression is a low mood that lasts for a long time, affecting your everyday life to the point where it is hard or impossible to have fun or enjoy life, or to do everyday things.

What causes depression?

We don’t know exactly what causes depression, but there are several ideas about causes of depression. This can vary between different people, and depression can be a result of a combination of different things. Some people find that they are depressed without an obvious reason.

Here are some possible causes of depression:

  • Difficult childhood experiences: abuse, neglect, loss, trauma or an unstable family situation may lead to depression later in life.
  • Life events and circumstances: stressful, traumatic or unwanted changes and events in life can trigger depression. This could be the loss of a loved one, end of a relationship, an unhappy or unhealthy relationship, illness, bullying, abuse, violence, or a big life change such as moving house, changing job, getting married or becoming pregnant.
  • Physical health problems and long-term conditions: if you have a condition or problem that is long-term (chronic), difficult to manage, life-changing or life-threatening, then it may cause depression. Hormonal problems, blood sugar and sleep problems can all cause depression.
  • Genetic factors are thought to increase your chances of suffering from depression, especially if you have a close relative with the condition.
  • Drugs and alcohol: excessive drinking and alcohol misuse can put you at greater risk of developing depression. Legal and illegal drugs can also affect your mental health.
  • Other mental health problems: experiencing anxiety, eating disorders and PTSD may mean you experience depression too.

Symptoms of depression

There are many different signs and symptoms of depression that people may experience. For some, these may be milder — you may feel low but will be able to live life as you normally would. For others, the symptoms of depression can be so severe that they are life-threatening because they can make the sufferer feel suicidal.

Here are some of the most common signs and symptoms of depression:

  • Feeling hopeless, helpless, or empty
  • Feeling guilty
  • Sleeping too much or difficulty sleeping
  • Feeling down, easily upset and teary
  • Difficulty concentrating, remembering or making decisions
  • Losing your appetite (or an increase in appetite)
  • Feeling tired and having less energy
  • Heavy, sluggish feelings
  • Lack of motivation
  • Losing interest or enjoyment in activities you used to enjoy
  • Low self-esteem/lack of confidence, feelings of worthlessness
  • Suicidal thoughts and feelings
  • Feeling restless, agitated or irritable
  • Losing your appetite (or an increase in appetite)
  • Loss of libido

How to treat depression

There are various treatments that have been found to help with depression.

Talk to your doctor if depression is affecting your day-to-day life and you feel unable to cope. They will ask you about your symptoms and your feelings to try to find out more, and then suggest one of the treatment options below:

  • Self-help resources such as a self-help programme guided by your doctor, computerised cognitive behavioural therapy (cCBT) or a physical activity programme (specifically for people with depression)
  • Talking treatments such as cognitive behavioural therapy (CBT), group-based CBT, interpersonal therapy (IPT)
  • Medication such as antidepressants if you have severe or long-lasting symptoms

Eating disorders

Eating disorders are characterised by an abnormal attitude towards food. This can involve unhealthy thoughts, extreme emotions, attitudes and behaviours involving food, weight and body shape. This can lead to the person with the eating disorder changing their eating habits and behaviour, making unhealthy choices about food that can result in damage to their health.

There are a number of different types of eating disorders, including:

  • Anorexia nervosa: when someone tries to keep their weight as low as possible, by starving themselves or exercising excessively. If you have anorexia, you may think you are overweight or fear becoming overweight, even when others say you aren’t.
  • Bulimia nervosa: when someone has bulimia, they will eat a lot of food (known as ‘binging’) and then do something to try to control their weight and avoid weight gain, such as deliberately being sick or using laxatives (known as ‘purging’).
  • Binge eating (BED): when someone feels compelled to overeat in a short period of time, on a regular basis. This can cause a lot of distress and the person may feel a lack of control when it comes to eating. It is sometimes described as compulsive eating.

There are certain myths about eating disorders and who can be affected — lots of people think that this is typically a problem experienced by younger women, or that people who have eating disorders will either be overweight or underweight. It is worth remembering that anyone — regardless of gender, age or weight — can be affected by eating problems.

What causes eating disorders?

Eating disorders are often blamed on the social pressures to be thin or look a certain way — particularly in young people. This could come from social circles, family members or wider social influences like social media, magazines, celebrities or influential figures.

However, the causes are usually more complex and can include a number of different factors:

  • Genetic factors such as a family history of eating disorders, depression or substance misuse
  • Being criticised, bullied or abused for eating habits, body shape or weight
  • The pressure to be slim from society or for a job or hobby (such as athletes, ballet dancers or models)
  • Psychological factors such as having obsessive or compulsive feelings, being vulnerable to depression and anxiety, low self-esteem, struggling to handle stress or control emotions, or being a perfectionist
  • Certain life experiences, such as trauma, sexual or emotional abuse, the death of a loved one
  • Difficult relationships with family members or friends
  • Stressful situations such as pressure or problems at school, university or work

As you can see, there are many reasons and risk factors when it comes to why people have eating disorders and how eating disorders start.

Symptoms of eating disorders

Symptoms can vary between individuals and depending on the eating disorder you have. It is also possible to experience more than one eating disorder or to experience some symptoms from each disorder.

Here are some more common psychological symptoms of eating disorders:

  • Feelings of shame and guilt
  • Feeling like you hate your body or that you are fat
  • Frightened of putting on weight
  • Feeling worthless or like you are never good enough, but that you have to be perfect
  • Feeling depressed, anxious, low and upset
  • Feeling scared of being found out by family and friends
  • Feeling lonely and isolated (especially if no one knows about your eating problem)
  • Sudden or extreme mood changes
  • Feeling out of control and trying to get control back
  • Feeling nervous or panicky around mealtimes
  • Losing interest or enjoyment in activities you used to enjoy
  • Difficulty concentrating
  • Feeling tired and disinterested in things
  • Feeling restless, agitated or irritable
  • Feeling numb

Here are some of the physical symptoms that can happen as a result of various eating disorders:

  • Weight changes (this could be weight loss, gain or fluctuations depending on the disorder)
  • Dehydration, which you might notice through bad skin and headaches
  • If you menstruate, your periods might become irregular or stop completely
  • Tiredness, weakness and lacking in energy
  • Feeling cold all the time
  • Nausea
  • Dizziness
  • Headaches
  • Stomach aches and pains
  • Damaged teeth and skin
  • Hair thinning or hair loss
  • Develop fine fuzzy hair on your arms and face
  • Sore throat (if you have bulimia)

Eating disorders treatment

The first step when it comes to how to treat eating disorders is to talk to your doctor. They will be able to refer you to more specialist services.

These services and treatments can help you develop balanced, healthy eating habits, as well as help you face the underlying issues which may be causing your eating problem.

Some typical treatments for eating disorders are online self-help programmes (you’ll receive support sessions alongside the programme to help you), talking treatments specifically for eating disorders such as CBT-ED (cognitive behavioural therapy for eating disorders), or family therapy (this is offered especially to younger people with anorexia).

OCD (obsessive-compulsive disorder)

Obsessive-compulsive disorder is a mental health diagnosis given to someone who experiences obsessive thoughts and compulsive behaviours.

People with OCD have repeated and constant thoughts or fears which are unwanted and unpleasant, causing feelings of anxiety, disgust or unease.

These disturbing and obsessive thoughts (known as ‘obsessions’) can cause sufferers to perform certain rituals or routines (known as ‘compulsions’) — a repetitive behaviour or act that the sufferer feels they need to carry out. This may temporarily relieve the unpleasant feelings and anxiety caused by the obsessive thought.

OCD symptoms can range from mild to severe. Some people with OCD may find that their obsessions and compulsions are manageable and don’t impact their lives that much, but for others, OCD can completely take over and make day-to-day life extremely difficult.

What causes OCD?

We don’t know exactly what causes obsessive-compulsive disorder, but there are thought to be a few main factors linked to the condition developing:

  • Biological factors like an imbalance of the brain chemical serotonin have been suggested to play a role in OCD developing (although we don’t know for certain if this is a cause of effect), as well as overactivity in certain areas of the brain.
  • Personality: certain personality traits such as being a ‘perfectionist’ — being meticulous and methodical with very high standards — or being prone to anxiety or worry may mean you are more likely to develop the condition.
  • Life events: something traumatic like abuse, neglect, social isolation, illness, bullying, or important life events such as bereavement, relationship breakups or childbirth could trigger OCD.

None of these factors can really fully explain every individual’s experience of OCD, but research suggests that the above are likely to be involved in causing the condition.

OCD Symptoms

OCD affects people differently, but there are some signs and symptoms to look out for, such as obsessive thoughts, anxiety, and compulsive behaviour (followed by a feeling of temporary relief before the cycle begins again).

Some common types of obsessive thoughts/obsessions include:

  • Fears about contamination, infection or disease
  • Worries about things being in the right place, in order, or symmetrical (and that bad things might happen if these things are not in order)
  • Concern over the safety and lives of friends and family
  • Worries that harm will come to yourself or others (or that you’ve already harmed someone by not doing something)
  • Unwelcome sexually disturbing images or thoughts
  • Violent intrusive thoughts (such as being violent to a loved one or other people, killing innocent people, or jumping in front of a train)
  • Relationship intrusive thoughts (these often appear as doubts about whether your partner really loves you, or that you love them, or that your relationship is ‘right’)

Some common types of compulsive behaviours/compulsions include:

  • Extreme cleaning and hand washing
  • Checking things repeatedly (such as checking doors are locked, or that a tap or light is off)
  • Counting things (like items in your handbag)
  • Repeating words silently and other mental rituals
  • Ordering and arranging
  • Hoarding
  • Asking others for reassurance
  • Overthinking
  • Thinking ‘neutralising’ thoughts to counter the obsessive thoughts
  • Avoiding places and situations that could trigger unwanted thoughts

Treatment for OCD

People with OCD are often reluctant to seek treatment because they feel ashamed, anxious, scared or embarrassed about their thoughts and what people will think about them. This can make it difficult to get help.

However, it is important to remember that your GP can help you to get treatment, which will help you to manage symptoms like these thoughts, and have a better quality of life.

OCD is usually treated with talking therapies such as cognitive behavioural therapy (CBT) and medication. You may also be offered exposure and response prevention (ERP) alongside CBT to help you deal with situations or things that make you anxious or frightened. This type of therapy is specifically designed to treat OCD — it encourages you to confront your obsessions and resist the urge to carry out compulsions through exposure to difficult or anxiety-inducing situations.


One in four people will experience mental illness in their lifetime, and there are some mental health disorders that are more common — some of which we have covered above.

Learning more about these common mental health disorders and their possible symptoms, causes and treatments might help you to feel more confident about talking and listening when it comes to mental health problems.

If you think you might have a mental health disorder, or someone close to you is struggling with a mental health disorder, then reading up on symptoms, diagnosis, treatment options, lifestyle changes and where to go for support can help. Your doctor will be able to help you take the next steps and get the support you need.


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