Depression is characterized by a persistent feeling of sadness and loss of interest in activities that were once enjoyable.

Schizophrenia is a serious mental illness characterized by hallucinations, delusions, disorganized speech, and flat affect.

Bipolar disorder is characterized by episodes of mania or hypomania and episodes of depression.

Generalized anxiety disorder is the most common anxiety disorder, characterized by excessive worry and anxiety that is difficult to control.

OCD is characterized by both obsessions (unwanted, intrusive thoughts) and compulsions (repetitive behaviors or mental acts).

PTSD is characterized by flashbacks, nightmares, avoidance, and other symptoms that develop after exposure to a traumatic event.

ADHD is characterized by inattention, hyperactivity, and impulsivity.

Binge eating disorder is the most common eating disorder, characterized by recurrent episodes of binge eating.

Substance use disorder is characterized by tolerance, withdrawal, cravings, and other symptoms that indicate a loss of control over substance use.

Personality disorder is characterized by rigid and inflexible personality traits and impaired social functioning.

Dissociative disorders are characterized by disruptions or discontinuities in consciousness, memory, identity, or perception.

Somatization disorder is characterized by physical symptoms that are not caused by a medical condition and excessive worry about physical symptoms.

Hypochondriasis is characterized by excessive worry about having a serious illness and repeatedly seeking medical attention.

Conversion disorder is characterized by physical symptoms that are not caused by a medical condition.

Factitious disorder is characterized by intentionally producing or feigning physical or psychological symptoms, lying about medical history, and seeking medical attention from multiple doctors.