TSR Wiki > Life > Health and Relationships > Mental Health > Mental Illnesses

Mental illnesses are psychological disorders which can cause a person extreme suffering. They affect around one in four people, although this may be higher if milder cases are also counted. Those who do not suffer from a mental disorder may feel that those who do are being irrational; but overcoming mental illness can be difficult and although the sufferer may understand their illness is irrational, they have great difficulty overcoming it.

A person is not defined by their disorder, as it is only a small part of who they are.


Mood disorders

These disorders, also called affective disorders, involve persistent feelings of sadness or periods of feeling overly happy, or fluctuations from extreme happiness to extreme sadness. The most common mood disorders are unipolar (major) depression and bipolar disorder.


Depression is a serious illness. Health professionals use the terms major depression, major depressive disorder, depressive illness or clinical depression to refer to something very different from the common experience of feeling miserable or fed-up for a short period of time. When you’re depressed, you may have feelings of extreme sadness that can last for a long time. These feelings are severe enough to interfere with your daily life, and can last for weeks or months, even years, rather than days. The most acutely affected are rendered mute and immobile (catatonic stupor), and psychotic features (delusions and hallucinations) are not uncommon at these more advanced stages.

Depression is quite a common condition, and about 15% of people will have a bout of severe depression at some point in their lives. However, the exact number of people with depression is hard to estimate because many people do not get help, or are not formally diagnosed with the condition.

Women are twice as likely to be diagnosed with depression, although over three-quarters of successful suicides are conducted by males, especially young and middle-aged men. This may, at least in part, be due to the fact that men tend to be more reluctant to seek help.

Depression can affect people of any age, including children. Studies have shown that 2% of teenagers in the UK are affected by depression.

People with a family history of depression are more likely to experience depression themselves, indicating a possible hereditary component to the illness. Depression affects people in many different ways and can cause a wide variety of physical, psychological and social symptoms.

A few people still think that depression is not a real illness and that it is a form of weakness or admission of failure. This is simply not true. Depression is a real illness with real effects, and it is certainly not a sign of failure. In fact, famous leaders, such as Winston Churchill, Abraham Lincoln and Mahatma Gandhi, all experienced bouts of depression.

Bipolar disorder

Bipolar disorder, also known as bipolar affective disorder, (and formerly manic-depressive illness) is a serious mental condition marked by extreme mood swings, from depressive lows to manic highs.

  • depression - where you feel very low, and
  • mania - where you feel very high; less severe mania is known as hypomania.

Both extremes of bipolar disorder have a number of other associated symptoms. Unlike simple mood swings, each extreme episode of bipolar disorder can last for several weeks or longer. The high and low phases of the illness are often so extreme that they interfere with everyday life.

The depression phase of bipolar disorder often comes first. Initially, you may be diagnosed with clinical depression before having a manic episode some time later (sometimes years later), after which your diagnosis might change. During an episode of depression, you may have overwhelming feelings of worthlessness which often lead to thoughts of suicide.

During a manic phase of bipolar disorder, you may feel very happy and have lots of ambitious plans and ideas. You may spend large amounts of money on things that you cannot afford. Not feeling like eating or sleeping, talking quickly, and becoming annoyed easily are also common characteristics of bipolar disorder. When symptoms are more serious, you may believe things that aren't true (delusions) and hear or see things that are not there (hallucinations).

There are two main types of this illness - bipolar I and bipolar II disorder. People with both types of bipolar disorder experience full depressive episodes but in bipolar II, the highs only reach hypomania instead of the full mania in bipolar I. Hypomania is similar to mania but you won’t lose touch with reality, be sectioned, or have difficulty functioning at work.

[Other forms of mood disorder]


In dysthymia, or persistent depressive disorder, people experience depression that is mild but lasts for a long time (generally at least two years). The symptoms of dysthymia and depression are similar and can have serious effects on the body, mind, and emotions. You may feel tired all the time, have difficulty concentrating and making decisions, and lose sleep and appetite.


Cyclothymia, informally called “bipolar-lite,” is a mild form of bipolar disorder. Someone who has this condition will experience ups and downs at a level more intense than most people but neither the highs nor lows reach hypomania or full depression.


Everyone experiences feelings of anxiety during their lifetime. For example, you may feel anxious about sitting an examination or having a medical test or job interview. It is natural to feel anxiety in these situations. However, some people may experience more persistent feelings of anxiety in situations which are not considered stressful by most people.

There are several forms of anxiety. These include generalised anxiety (GAD), social anxiety (SAnD), post traumatic stress (PTSD) and obsessive compulsive (OCD) disorders.

Generalised anxiety disorder (GAD)

Generalised anxiety disorder is a long-term condition that causes people feel anxious about a wide range of situations and issues, rather than one specific event. People with GAD find that they feel anxious on most days, and this can become a serious problem. The condition usually leads to psychological and physical symptoms.

GAD affects approximately one in fifty people at some stage during their lifetime. The condition is slightly more common among women.

GAD may significantly affect the quality of life experienced by a person, which may lead to depression. There are various treatments available, which are able to ease both your psychological and physical symptoms. The most successful therapeutic options include CBT (cognitive behavioural therapy) and applied relaxation. Medication may also be used as a treatment, for example SSRIs (e.g. Sertraline, Escitalopram) or SNRIs (Venlafaxine, Duloxetine).

Social anxiety disorder (SAnD)

Social anxiety disorder, also known as social phobia, is the fear of social situations which may need to be faced on a daily basis. If the sufferer feels they are being judged or watched by others, they may feel embarrassed and become self-conscious.

The severity of SAnD varies. A mild form may cause discomfort in specific situations such as speaking in front of large groups of people, this may cause some avoidance but sufferers are generally still able to cope with less intense social situations. A severe form of SAnD can lead to avoidance of many social situations such as lectures, social gatherings etc. In addition, it may cause extremely uncomfortable physical symptoms when faced with feared situations.

It is among the most common mental disorders, and is the most common anxiety disorder. It is experienced by approximately one in eight people at some point in their lifetime but rarely becomes a long-term condition. Those who suffer in the long-term become more vulnerable to other psychological disorders such as depression.

The cause of the condition is mostly environmental, such as having learned behaviours during childhood. Genetic factors may cause someone to be more vulnerable to the disorder. There is a possibility of SAnD being caused due to overprotective parents.

SAnD is a condition which tends to persist if not treated. Unfortunately not enough people seek treatment due to embarrassment, however those who do are usually treated successfully. There are various treatments available such as CBT (cognitive behavioural therapy) which may be the most effective treatment; other options include hypnotherapy, medication and self-help. Medication is commonly used, particularly those in the SSRI class (e.g. Paroxetine, Sertraline, Escitalopram), however other options such as Benzodiazepines may be used for the short-term relief of extreme anxiety (e.g. Diazepam, Clonazepam).

A mild form of SAnD does not usually require treatment such as medication. It is best to use psychological methods of treatment in these cases.

Obsessive compulsive disorder (OCD)

Obsessive compulsive disorder is a long-term condition which causes a person to experience unpleasant thoughts and compulsions which leads to the person feeling the constant urge to repeatedly perform an activity. The compulsion relieves the anxiety from the obsessive thought, however this is only a short-lived relief and because compulsions tend to be repeated they lead to frustration. A vicious cycle tends to occur with those who suffer.

The majority of people have obsessions such as making sure the door to their house is closed, however these do not interfere with their daily life. Those who suffer severe forms of OCD may feel that their life is being controlled by their condition. The condition also tends to be associated with depression and/or social anxiety.

The most common obsessions include the fear of not preventing harm, going against your religion, having intrusive sexual thoughts, being contaminated, objects not being symmetrical and illness. The person may also only purchase a certain number of items from a market (e.g. two of each item), constantly check an email before sending it or wash their hands very frequently.

The condition tends to persist without treatment. Unfortunately not enough people seek treatment due to embarrassment, however those who do are usually treated successfully. The recommended treatment is CBT (cognitive behavioural therapy) and/or medication. CBT works on the obsessions and prevents the person using compulsions as a method of neutralising them. The prescribed medication would usually be an SSRI such as Fluvoxamine, Citalopram or Sertraline which are some examples of effective medication.

Post traumatic stress disorder (PTSD)

PTSD is a condition that can develop following a traumatic and/or terrifying event, such as a sexual or physical assault, the unexpected death of a loved one, or a natural disaster. People with PTSD often have lasting and frightening thoughts and memories of the event, and tend to be emotionally numb.

Diagnostic symptoms include re-experiencing original trauma(s), by means of flashbacks or nightmares; avoidance of stimuli associated with the trauma; and increased arousal, such as difficulty falling or staying asleep, anger, and hypervigilance. Formal diagnostic criteria (both DSM-IV and ICD-9) require that the symptoms last more than one month and cause significant impairment in social, occupational, or other important areas of functioning (e.g. problems with work and/or relationships)


Agoraphobia is the fear of being unable to escape from a public place. The condition may cause those who suffer to avoid public places. The sufferer may also fear being scrutinised or feeling helpless in these situations.

Those with the condition may fear entering shops or crowds, travelling on trains or planes, being on a bridge or in a lift, or being anywhere far from their home. Being in a feared place may cause the person extreme discomfort. The anxiety often leads to physical symptoms such as shaking, sweating, palpitations, and also the desire to leave. In extreme circumstances, a panic attack may be triggered.

The severity of the condition varies. Those who suffer mild agoraphobia are usually able to attend many places without feeling overwhelmingly fearful, however severe agoraphobia may cause the person to isolate themselves from the outside world which can greatly affect their life.

The effects of agoraphobia are similar to those of SAnD, however the causes are different. There is a possibility of the person developing depression if they are 'withdrawing' from the world.

Treatment is available in both psychological and psychiatric forms. As with most anxiety disorders, CBT is the most effective form of phycological treatment and possibly the most effective treatment for agoraphobia. Medication is also effective, particularly those in the SSRI/SNRI class (e.g. Sertraline, Fluoxetine, Paroxetine), benzodiazepines are effective for the short-term relief of agoraphobia, particularly alprazolam and clonazepam.

Panic disorder

Panic disorder is characterised by having regular panic attacks which may occur due to several reasons or no reason whatsoever. Everyone will feel panic at certain points within their lifetime, however these are not regular and rarely occur for no reason.

A panic attack is extremely uncomfortable, causing phycological and physical symptoms such as sweating, uncontrollable trembling, flushing and nausea. The severity of a panic attack varies, some being mild leading to few if any physical symptoms, whilst others causing extreme symptoms. The length of a panic attack also varies, they usually last five to ten minutes but may even last hours.

Approximately one in ten people will experience panic attacks occasionally, however one in fifty are diagnosed with panic disorder. A panic attack may be triggered by other anxiety disorders such as OCD, SAnD, GAD and/or a specific phobia.

Psychological therapy is commonly used for the treatment of panic disorder, CBT in particular. Medication such as SSRIs (e.g. Sertraline, Paroxetine) or Pregabalin may also be used to treat panic disorder.

Specific phobia

A specific phobia is characterised by an intense fear of a specific object and/or situation. For example, the fear of snakes, spiders, heights, public speaking, darkness or failure may cause anxiety.

The severity of the phobia varies. It is common for a person to have a general fear of something, however someone with a phobia may experience extremely uncomfortable symptoms when faced with the feared event. In a majority of cases, the fear does not severely affect the life of a person, however extreme cases may lead to a panic attack.

A specific phobia can be managed with therapy such as counselling, hypnosis or CBT (cognitive behavioural therapy). In severe cases, medications in the SSRI/SNRI classes may be used for long-term treatment, for short-term relief benzodiazepines/beta-blockers may be used instead.

Psychotic disorders

These are a group of serious illnesses that affect the mind. These illnesses alter a person's ability to think clearly, make good judgments, respond emotionally, communicate effectively, understand reality, and behave appropriately. When symptoms are severe, people with psychotic disorders have difficulty staying in touch with reality and often are unable to meet the ordinary demands of daily life. However, even the most severe psychotic disorders usually are treatable.


Schizophrenia is a severe and chronic chronic mental health condition that causes a range of different psychological symptoms. These include:

  • hallucinations - hearing or seeing things that do not exist
  • delusions - believing in things that are untrue.

Hallucinations and delusions are often referred to as psychotic symptoms or symptoms of psychosis. Psychosis is when somebody is unable to distinguish between reality and their imagination. Another, very important symptom of psychosis characteristic of schizophrenia is known as "formal thought disorder" - here, speech may become illogical and hard to understand; ideas that might not have any clear connection with the other might be haphazardly put together. This can make communication very difficult.

Catatonic or bizarre behaviour and "negative symptoms" (for example, lack of motivation and will, limited emotions) may also be seen.

The exact cause of schizophrenia is unknown. However, most experts believe that the condition is caused by a combination of genetic and environmental factors.

Schizophrenia is one of the most common serious mental health conditions. One in 100 people will experience at least one episode of acute schizophrenia during their lifetime. It may be slightly more common among males than women. Symptoms also tend to be more severe in men.

One misconception is that people with schizophrenia have a split or dual personality, acting perfectly normal one minute and then irrationally or bizarrely the next. However, this is totally untrue. Schizophrenia is a Greek word that means 'split mind', but the term was first used long before the condition was properly understood.

It would be more accurate to say that people with schizophrenia have a mind that can experience episodes of dysfunction and disorder.

Another misconception about schizophrenia is that people who have the condition are violent. Again, there is little evidence to back this up. Acts of violence committed by people with schizophrenia get a great deal of high-profile media coverage, and this can give the impression that such acts happen frequently when they are in fact very rare.

A person with schizophrenia is far more likely to be the victim of violent crime, rather than the instigator. Experts at the Royal College of Psychiatrists estimate that if schizophrenia could be cured overnight, the rate of violent crime in England would only drop by 1%.


This is a type of schizophrenia that starts late in life and occurs in the elderly population.

Schizoaffective disorder

A person with this disorder has both a mood disorder and psychosis, and the voices or false beliefs are more independent of what is going on with their mood, and may be present even if their mood is stable.

Substance-induced psychotic disorder

This condition is caused by the use of or withdrawal from some substances, such as alcohol and crack cocaine, that may cause hallucinations, delusions, or confused speech.

Dissociative disorders

People with these disorders suffer severe disturbances or changes in memory, consciousness, identity, and general awareness of themselves and their surroundings. These disorders usually are associated with overwhelming stress, which may be the result of traumatic events, accidents or disasters that may be experienced or witnessed by the individual

Dissociative Identity Disorder

Formerly known as multiple personality disorder, (and, colloquially, "split personality"), Dissociative Identity Disorder is an extreme mental illness that is characterised by the existence of two or more distinct personality states that have the capacity to take control of the body, and the inability to recall personal information too great to be explained by ordinary forgetfulness.

The condition cannot be due to the effect of substances or a medical condition.

There may be accompanying symptoms such as depression, anxiety, obsessive/compulsive behaviour and eating disorders.

Some cases undoubtedly arise from continued and repeated sexual and/or physical abuse beginning in early childhood. In such cases DID is a defensive mechanism that protects the child from the physical and emotional pain associated with abuse by separating a part of the child's mind or consciousness to deal with the trauma of the abuse.

Over time and repeated abuse, these separate parts establish identities of their own. This is a protective measure put down by the brain to prevent too much damage to the host.

People with DID have been shown to be highly susceptible to dissociation, are generally of above average intelligence, and highly creative.

The object of treatment is to stabilize the person and lessen the degree of dissociation - a process called integration. Alternatively they can opt to gain a level of co-consciousness wherein the members of the system will all co-habit and work together within the one body.

According to some studies, the 'average' person diagnosed with DID spends seven years in the mental health system before being properly diagnosed, due to misdiagnosis and lack of training on the part of therapists to spot the disorder.

Dissociative fugue

Dissociative fugue is characterized by sudden, unexpected travels from the home or workplace with an inability to recall some or all of one's past. Some of these patients assume a new identity or are confused about their own identity. They seem to be running away from something of which they are unaware.

After the fugue episode resolves, patients are unable to remember the events of the state. Although moving occurs in other disorders, in fugue it is purposeful and is not enacted in a confused or dazed state. In a typical case, the fugue is brief, with purposeful travel, and with limited contact with others. Approximately 0.2% of the general population has dissociative fugue.

DSM-IV-TR diagnostic criteria for fugue require that the predominant disturbance is sudden, unexpected travel away from home or one's workplace coupled with the inability to recall one's past. Also, the person has confusion about personal identity or assumes a new identity. The disturbance does not occur exclusively during the course of DID and is not due to the direct physiologic effects of a substance or medication. The symptoms also must cause clinically significant distress or impairment in social, occupational, or other important areas of functioning.

Depersonalisation disorder

Depersonalization is characterized by feelings that the objects of the external environment are changing shape and size, or that people are automated and inhuman, and features detachment as a major defense. Depersonalization disorder usually begins in adolescence; typically, patients have continuous symptoms. Onset can be sudden or gradual. An estimated 2.4% of the general population meets the diagnostic criteria for this disorder. However, the prevalence rate is questioned by many clinicians and may be lower. This disorder frequently coexists with mood, anxiety, and psychotic disorders.

Dissociative disorder not otherwise specified

DDNOS is a category of disorders that manifest with dissociative symptoms but fail to meet the diagnostic criteria for any of the dissociative syndromes described.

An example of DDNOS is Ganser syndrome. This entity occurs primarily in men (80%) and is currently regarded as a dissociative means of withdrawal from a traumatic or stressful circumstance. It is characterized by absurd or approximate responses to interview dialogue, a dazed or clouded level of consciousness, somatic conversion symptoms (eg, pseudoparalysis), hallucinations, and, frequently, anterograde amnesia regarding the episode. Patients who demonstrate this phenomenon may have a past history of abuse or other trauma. In general, these patients are at higher risk for dissociative symptoms when under stress.

Eating Disorders

Problems with food can begin when it is used to cope with those times when you are anxious, angry, lonely, ashamed or sad.

Food becomes a problem when it's used to help you to cope with painful situations or feelings, or to relieve stress, perhaps without you even realising it.

It is unlikely that an eating disorder will be the result of one single cause. It is much more likely to be a combination of many factors, events, feelings or pressures that lead to you feeling unable to cope. These can include: low self-esteem, family relationships, problems with friends, the death of someone special, problems at work, college or at university, lack of confidence, or sexual or emotional abuse. Many people talk about simply feeling ‘too fat’ or ‘not good enough’.

People with eating disorders often say that the eating disorder is the only way they feel they can stay in control of their life. But as time goes on it isn’t really you who is in control – it is the eating disorder. Some people also find they are affected by an urge to harm themselves or misuse alcohol or drugs.

Anyone can develop an eating disorder, regardless of age, sex, cultural or racial background. But the people most likely to be affected tend to be young women, particularly between the ages of 15 and 25.

Traumatic events can sometimes trigger an eating disorder: bereavement, being bullied or abused, an upheaval in the family (such as divorce), long-term illness or concerns over sexuality. Someone with a long-term illness or disability (such as diabetes, depression, blindness or deafness) may also experience eating problems.


Anorexia nervosa means 'loss of appetite for nervous reasons'. In fact, people with anorexia nervosa may have a normal appetite. But they have lost the ability to allow themselves to satisfy their appetite. They probably:

  • restrict the amount they eat and drink, sometimes to a dangerous level,
  • exercise to burn off what they perceive to be excess calories, or
  • focus on food in an attempt to cope with life (not to starve themselves to death).

Anorexia is a way for someone to demonstrate that they are in control of their body weight and shape. Ultimately, however, the disorder itself takes control and the chemical changes in the body affect the brain and distort the person's thinking. It makes it almost impossible to make rational decisions about food.


The term bulimia nervosa means literally ‘the nervous hunger of an ox’. The hunger, however, is really an emotional need that cannot be satisfied by food alone. After binge-eating a large quantity of food to fill the emotional or hunger gap, there is an urge to immediately get rid of the food by vomiting or taking laxatives (or both), by starving or reducing food intake, or by working off the calories with exercise in an attempt not to gain weight.

Bulimia is more difficult to notice as someone with bulimia will tend not to lose weight dramatically, or their weight will fluctuate. You may not recognise the illness in a friend, so it can persist for many years undetected. Binge eating disorder Binge eating symptoms are also present in bulimia. The formal diagnosis criteria are similar in that subjects must binge at least twice per week for a minimum period of three months. Unlike in bulimia, those with BED do not purge, fast or engage in strenous exercise after binge eating. Binge eating disorder is similar to, but it is distinct from, compulsive overeating. Those with BED do not have a compulsion to overeat and do not spend a great deal of time fantasizing about food. On the contrary, some people with binge eating disorder have very negative feelings about food. As with other eating disorders, binge eating is an "expressive disorder" — a disorder that is an expression of deeper psychological problems. Some researchers believe BED is a milder form, or subset of bulimia nervosa, while others argue that it is its own distinct disorder.

Compulsive overeating

An individual suffering from compulsive overeating disorder engages in frequent episodes of uncontrolled eating, or binging, during which they may feel frenzied or out of control, often consuming food past the point of being comfortably full. Bingeing in this way is generally followed by feelings of guilt and depression. Unlike individuals with bulimia, compulsive overeaters do not attempt to compensate for their bingeing with purging behaviors such as fasting, laxative use or vomiting. Compulsive overeaters will typically eat when they are not hungry. Their obsession is demonstrated in that they spend excessive amounts of time and thought devoted to food, and secretly plan or fantasize about eating alone. Compulsive overeating usually leads to weight gain and obesity, but not everyone who is obese is also a compulsive overeater.

In addition to binge eating, compulsive overeaters can also engage in grazing behavior, during which they return to pick at food throughout the day. This results in a large overall number of calories consumed even if the quantities eaten at any one time may be small.

Eating disorder not otherwise specified (EDNOS)

This category is frequently used for people who meet some, but not all, of the diagnostic criteria for anorexia or bulimia. A sufferer may experience episodes of binging and purging, but may not do so frequently enough to warrant a diagnosis of bulimia nervosa. A person may also engage in binging episodes without the use of inappropriate compensatory behaviors; this is referred to as binge eating disorder.

People diagnosed with EDNOS may frequently switch between different eating disorders, or may with time fit all diagnostic criteria for anorexia or bulimia.

Orthorexia nervosa

A term used to denote an eating disorder characterized by excessive focus on eating healthy foods. In rare cases, this focus may turn into a fixation so extreme that it can lead to severe malnutrition or even death. Unlike anorexia and bulimia where the goal is weight loss or control here the goal of the person is to feel pure, healthy and natural.

Impulse control and addiction disorders

People with impulse control disorders are unable to resist urges, or impulses, to perform acts that could be harmful to themselves or others. Pyromania (starting fires), kleptomania (stealing) and compulsive gambling are examples of impulse control disorders. Alcohol and drugs are common objects of addictions. Often, people with these disorders become so involved with the objects of their addiction that they begin to ignore responsibilities and relationships.

Adjustment disorder

Adjustment disorder occurs when a person develops emotional or behavioral symptoms in response to a stressful event or situation. The stressors may include natural disasters, such as an earthquake or tornado; events or crises, such as a car accident or the diagnosis of a major illness; or interpersonal problems, such as a divorce, death of a loved one, loss of a job or a problem with substance abuse. Adjustment disorder usually begins within three months of the event or situation and ends within six months after the stressor stops or is eliminated.

Personality disorders

People with personality disorders have extreme and inflexible personality traits that are distressing to the person and/or cause problems in work, school or social relationships. In addition, the person's patterns of thinking and behaviour significantly differ from the expectations of society and are so rigid that they interfere with the person's normal functioning. They are split into three clusters - A (odd/eccentric), B (emotional/impulsive) and C (anxious), and altogether there are currently ten recognised forms: namely, schizoid, schizotypal and paranoid; borderline, histrionic, narcissistic and anti-social (psychopathic); and obsessive-compulsive, dependent and avoidant. There is a marked predominance of males for all but borderline, histrionic and dependent personality disorders, which are more common in women.


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