There are many various illnesses which can be recognized as mental illnesses. The more common types include:
- Anxiety disorders: People with anxiety disorders react to certain objects or situations with fear and terror, in addition to physical signs of fear or panic, corresponding to a racing heart and sweating. An anxiety disorder is diagnosed when the person's response will not be appropriate to the situation, when the person cannot control the response, or when the anxiety interferes with normal functioning. Anxiety disorders include generalized anxiety disorder, panic disorder, social anxiety disorder and specific phobias.
- Mood disorders: These disorders, also called mood disorders, involve persistent feelings of sadness or periods of excessive happiness, or fluctuations from extreme happiness to extreme sadness. The commonest mood disorders are depression, bipolar disorder, and cyclothymic disorder.
- Psychotic disorders: Psychotic disorders end in impaired consciousness and pondering. Two of essentially the most common symptoms of psychotic disorders are hallucinations – experiencing images or sounds that usually are not real, corresponding to hearing voices – and delusions, that are false, fixed beliefs that the sufferer believes to be false despite evidential evidence true accepts opposite. Schizophrenia is an example of a psychotic disorder.
- Eating disorders: Eating disorders involve extreme emotions, attitudes, and behaviors related to weight and food. Anorexia nervosa, bulimia nervosa and binge eating disorder are essentially the most common eating disorders.
- Impulse control and addiction disorders: People with impulse control disorders are unable to withstand urges or impulses to perform actions that may very well be harmful to themselves or others. Examples of impulse control disorders include pyromania (making fire), kleptomania (stealing), and gambling addiction. Alcohol and medicines are common objects of addiction. People with these disorders often turn out to be so preoccupied with the objects of their addiction that they start to disregard responsibilities and relationships.
- Personality disorders: People with personality disorders have extreme and inflexible personality traits which can be stressful for the person and/or cause problems at work, school, or social relationships. In addition, the person's thought and behavior patterns deviate significantly from society's expectations and are so rigid that they interfere with the person's normal functioning. Examples include antisocial personality disorder, obsessive-compulsive personality disorder, histrionic personality disorder, schizoid personality disorder, and paranoid personality disorder.
- Obsessive compulsive disorder (OCD): People with OCD are tormented by constant thoughts or fears that cause them to perform certain rituals or routines. The disturbing thoughts are called obsessions and the rituals are called compulsions. An example is an individual with an unfounded fear of germs who always washes their hands.
- Post-traumatic stress disorder (PTSD): PTSD is a condition that may develop after a traumatic and/or horrific event, corresponding to a sexual or physical assault, the unexpected death of a loved one, or a natural disaster. People with PTSD often have persistent and frightening thoughts and memories of the event and are likely to be emotionally numb.
Other, less common sorts of mental illness include:
- Stress response syndromes (formerly called adjustment disorders): Stress response syndromes occur when an individual develops emotional or behavioral symptoms in response to a stressful event or situation. Stressors can include natural disasters corresponding to an earthquake or tornado; events or crises corresponding to a automobile accident or the diagnosis of a serious illness; or interpersonal problems corresponding to a divorce, the death of a loved one, the lack of a job, or a substance abuse problem. Stress response syndromes normally begin inside three months of the event or situation and end inside six months of the stressor being stopped or eliminated.
- Dissociative disorders: People with these disorders experience severe impairment or changes in memory, consciousness, identity, and general perception of themselves and their surroundings. These disorders are often related to overwhelming stress, which stands out as the results of traumatic events, accidents or disasters that the person has experienced or witnessed. Examples of dissociative disorders are dissociative identity disorder, previously also called multiple personality disorder or “split personality,” and depersonalization disorder.
- Factual disruptions: Factitious disorders are conditions through which an individual knowingly and intentionally causes or complains of physical and/or emotional symptoms with a purpose to place the person within the role of a patient or needy person.
- Sexual and Gender Disorders: These include disorders that affect sexual desire, sexual performance and sexual behavior. Sexual dysfunction, gender identity disorder, and paraphilias are examples of sexual and gender disorders.
- Somatic symptom disorders: An individual with a somatic symptom disorder, formerly often known as a psychosomatic disorder or somatoform disorder, experiences physical symptoms of illness or pain with an excessive and disproportionate level of distress, no matter whether or not a health care provider can discover a medical cause for the symptoms.
- Tic disorders: People with tic disorders make noises or exhibit inappropriate body movements which can be repetitive, rapid, sudden, and/or uncontrollable. (Sounds which can be produced involuntarily are called vocal tics.) Tourette syndrome is an example of a tic disorder.
Other diseases or conditions, including various sleep-related problems and plenty of types of dementia, including Alzheimer's disease, are sometimes classified as mental illnesses because they affect the brain.