Mood disorder in the context of "Major depressive disorder"

Fatigue is a state of being without energy for a prolonged period of time. Fatigue is used in two contexts: in the medical sense, and in the sense of normal tiredness.

In the medical sense, fatigue is seen as a symptom, and is sometimes associated with medical conditions including autoimmune disease, organ failure, chronic pain conditions, mood disorders, heart disease, infectious diseases, and post-infectious-disease states. However, fatigue is complex and in up to a third of primary care cases no medical or psychiatric diagnosis is found.

Conversion disorder (CD) was a formerly diagnosed psychiatric disorder characterized by abnormal sensory experiences and movement problems during periods of high psychological stress. Individuals diagnosed with CD presented with highly distressing neurological symptoms such as numbness, blindness, paralysis, or convulsions, none of which were consistent with a well-established organic cause and could be traced back to a psychological trigger. CD is no longer a diagnosis in the WHO's ICD-11 or APA's DSM-5 and was superseded by functional neurologic disorder (FND), a similar diagnosis that notably removed the requirement for a psychological stressor to be present.

It was thought that these symptoms arise in response to stressful situations affecting a patient's mental health. Individuals diagnosed with conversion disorder have a greater chance of experiencing certain psychiatric disorders including anxiety disorders, mood disorders, and personality disorders compared to those diagnosed with neurological disorders.

Bad breath, also known as halitosis, is a symptom in which a noticeably unpleasant breath odour is present. It can result in anxiety among those affected. It is also associated with depression and symptoms of obsessive compulsive disorder.

The concerns of bad breath may be divided into genuine and non-genuine cases. Of those who have genuine bad breath, about 85% of cases come from inside the mouth. The remaining cases are believed to be due to disorders in the nose, sinuses, throat, lungs, esophagus, or stomach. Rarely, bad breath can be due to an underlying medical condition such as liver failure or ketoacidosis. Non-genuine cases occur when someone complains of having bad breath, but other people cannot detect it. This is estimated to make up between 5% and 72% of cases.

Neuroticism or negativity is a personality trait associated with negative emotions. It is one of the Big Five traits. People high in neuroticism experience negative emotions like fear, anger, shame, envy, or depression more often and more intensely than those who score low on neuroticism. Highly neurotic people have more trouble coping with stressful events, are more likely to insult or lash out at others, and are more likely to interpret ordinary situations (like minor frustrations) as hopelessly difficult. Neuroticism is closely-related to mood disorders such as anxiety and depression.

Individuals who score low in neuroticism tend to be more emotionally stable and less reactive to stress. They tend to be calm, even-tempered, and less likely to feel tense or rattled. Although they are low in negative emotion, they are not necessarily high in positive emotions, which are more commonly associated with extraversion and agreeableness. Neurotic extroverts, for example, would experience high levels of both positive and negative emotional states, a kind of "emotional roller coaster".

Dialectical behavior therapy (DBT) is an evidence-based psychotherapy that began with efforts to treat personality disorders and interpersonal conflicts. Evidence suggests that DBT can be useful in treating mood disorders and suicidal ideation as well as for changing behavioral patterns such as self-harm and substance use. DBT evolved into a process in which the therapist and client work with acceptance and change-oriented strategies and ultimately balance and synthesize them—comparable to the philosophical dialectical process of thesis and antithesis, followed by synthesis.

This approach was developed by Marsha M. Linehan, a psychology researcher at the University of Washington. She defines it as "a synthesis or integration of opposites". DBT was designed to help people increase their emotional and cognitive regulation by learning about the triggers that lead to reactive states and by helping to assess which coping skills to apply in the sequence of events, thoughts, feelings, and behaviors to help avoid undesired reactions. Linehan later disclosed to the public her own struggles and belief that she suffers from borderline personality disorder.