A Comprehensive List of Mental Illnesses and Their Symptoms

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Mental health awareness has surged into the spotlight in recent years, prompting a significant push to destigmatize the diverse spectrum of mental illnesses. Although we’ve made strides, the complexity of mental health continues to be widely misunderstood. With countless individuals affected directly or indirectly by mental health challenges, a comprehensive understanding is more crucial than ever.

In this extensive compilation, we’re unpacking a detailed look at various mental illnesses, each with its distinctive symptoms and characteristics. This resource is invaluable for mental health advocates, medical professionals, and caregivers who seek to broaden their knowledge and enhance their capacity to support those in need.

Neurodevelopmental Disorders

Autism Spectrum Disorder (ASD)

Symptoms:

  • Impaired communication and social interaction
  • Repetitive behaviors and intense focus on certain areas
  • Difficulty in social environments and reading social cues
  • Sensory sensitivities
  • Aversion to change and insistence on routine

Attention-Deficit/Hyperactivity Disorder (ADHD)

Symptoms:

  • Inattention and difficulty concentrating
  • Hyperactivity and impulsivity
  • Restlessness and difficulty sitting still
  • Forgetfulness and poor organizational skills
  • Frequent shifting from one uncompleted activity to another

Schizophrenia Spectrum and Other Psychotic Disorders

Schizophrenia

Symptoms:

  • Delusions
  • Hallucinations
  • Disorganized thinking and speech
  • Agitation and lack of pleasure in activities
  • Social withdrawal

Schizoaffective Disorder

Symptoms:

  • Schizophrenia symptoms alongside a mood disorder
  • Major depressive episodes
  • Manic episodes

Delusional Disorder

Symptoms:

  • Delusions without other prominent psychotic symptoms
  • The central theme of the delusion is typically persistent
  • Functioning in daily life not significantly impaired

Brief Psychotic Disorder

Symptoms:

  • Sudden onset of psychotic symptoms
  • Symptoms may follow a significant stressor
  • Episodes last at least 1 day but less than 1 month

Schizophreniform Disorder

Symptoms:

  • Typically involves the sudden onset of schizophrenia symptoms
  • Episodes last at least 1 month but less than 6 months

Bipolar and Related Disorders

Bipolar I Disorder

Symptoms:

  • At least one manic episode that may be preceded or followed by hypomanic or major depressive episodes
  • Manic episodes involve elevated, expansive, or irritable mood, and increased energy

Bipolar II Disorder

Symptoms:

  • Consists of a pattern of depressive episodes and hypomanic episodes
  • No full-blown manic or mixed episodes

Cyclothymic Disorder

Symptoms:

  • Numerous periods with hypomanic symptoms and periods with depressive symptoms
  • Symptoms do not meet the criteria for a major depressive episode, a manic episode, or a hypomanic episode

Depressive Disorders

Major Depressive Disorder (MDD)

Symptoms:

  • Sadness or a depressed mood
  • Loss of interest in previously enjoyed activities
  • Significant changes in appetite and energy
  • Disruption in sleep patterns
  • Feelings of worthlessness or guilt
  • Concentration difficulties
  • Suicidal thoughts or behaviors

Persistent Depressive Disorder (Dysthymia)

Symptoms:

  • Chronic low-level depression
  • Disruption in sleep patterns
  • Poor appetite or overeating
  • Low self-esteem
  • Difficulty concentrating and decision-making

Premenstrual Dysphoric Disorder

Symptoms:

  • Marked changes in mood and severe anxiety before menstruation
  • Severe mood swings and irritability
  • Depressed mood, feeling hopeless or self-critical
  • Tension and anxiety
  • Decreased interest in usual activities
  • Difficulty concentrating
  • Change in appetite, overeating, or food cravings
  • Sleep disturbance
  • Physical symptoms, such as breast tenderness or bloating

Anxiety Disorders

Generalized Anxiety Disorder (GAD)

Symptoms:

  • Excessive worry or anxiety
  • Difficulty controlling worry
  • Restlessness or feeling on edge
  • Easily fatigued
  • Difficulty concentrating or mind going blank
  • Irritability
  • Muscle tension
  • Difficulty sleeping

Panic Disorder

Symptoms:

  • Sudden and repeated attacks of intense fear
  • Feelings of being out of control during a panic attack
  • Intense worries about when the next attack will happen
  • Fear or avoidance of places where panic attacks have occurred in the past

Agoraphobia

Symptoms:

  • Fear of places and situations that might cause panic, helplessness, or embarrassment
  • Avoidance of such situations
  • In severe cases, an individual can become housebound

Social Anxiety Disorder

Symptoms:

  • Intense fear of social situations
  • Concern about being judged negatively by others
  • Avoidance of social interactions

Obsessive-Compulsive and Related Disorders

Obsessive-Compulsive Disorder (OCD)

Symptoms:

  • Obsessions are intrusive, unwanted thoughts
  • Compulsions are behaviors or actions meant to neutralize the obsessions

Body Dysmorphic Disorder

Symptoms:

  • Obsession with a perceived flaw in appearance that others might not notice
  • Engaging in behaviors such as frequently checking the mirror, grooming, skin-picking, or reassurance seeking
  • Avoidance of social situations to hide the perceived flaw

Hoarding Disorder

Symptoms:

  • Persistently having difficulty discarding possessions, regardless of their actual value
  • Accumulation of possessions that clutter active living areas
  • Significant distress associated with discarding items

Trauma- and Stressor-Related Disorders

Posttraumatic Stress Disorder (PTSD)

Symptoms:

  • Intrusive memories of the traumatic event
  • Flashbacks, reliving the trauma as if it were happening again
  • Emotional numbness
  • Avoidance of places, people, and activities that remind of the traumatic event
  • Hyperarousal, feeling keyed up and on high alert

Acute Stress Disorder

Symptoms:

  • PTSD symptoms that occur shortly after experiencing a traumatic event and lasting for at least 3 days

Dissociative Disorders

Dissociative Identity Disorder (DID)

Symptoms:

  • Two or more distinct personality states or experiences of possession
  • Recurrent gaps in the recall of everyday events, personal information, or traumatic events

Depersonalization-Derealization Disorder

Symptoms:

  • Persistent or recurrent experiences of feeling detached from one’s mental processes or body
  • Feeling like one is in a dream or watching things happen without feeling in control

Dissociative Amnesia

Symptoms:

  • Inability to recall important personal information, usually of a traumatic or stressful nature
  • Not due to the effects of a substance or a neurological or other medical condition

Somatic Symptom and Related Disorders

Somatic Symptom Disorder

Symptoms:

  • One or more distressing, persistent, and excessive somatic (bodily) symptoms
  • Excessive thoughts, feelings, or behaviors related to the somatic symptoms or associated health concerns

Illness Anxiety Disorder (Hypochondriasis)

Symptoms:

  • Preoccupation with having or acquiring a serious illness
  • Serious anxiety about health
  • Excessive health-related behaviors

Feeding and Eating Disorders

Anorexia Nervosa

Symptoms:

  • Restriction of energy intake relative to requirements leading to a significantly low body weight
  • Intense fear of gaining weight or becoming fat
  • Distorted body image, including denial of the severity of low body weight

Bulimia Nervosa

Symptoms:

  • Recurrent episodes of binge eating, characterized by both of the following:
  • Eating, in a discrete period of time, an amount of food that is definitely larger than what most individuals would eat in a similar period of time under similar circumstances
  • A sense of lack of control over eating during the episode
  • Recurrent inappropriate compensatory behaviors to prevent weight gain

Binge-Eating Disorder

Symptoms:

  • Recurrent episodes of binge eating
  • Eating much more rapidly than normal
  • Eating until feeling uncomfortably full
  • Eating large amounts of food when not feeling physically hungry
  • Eating alone because of feeling embarrassed by how much one is eating
  • Feeling disgusted with oneself, depressed or very guilty afterward

Sleep-Wake Disorders

Insomnia Disorder

Symptoms:

  • Difficulty initiating sleep
  • Difficulty maintaining sleep
  • Early-morning awakening with the inability to return to sleep
  • Nonrestorative sleep

Hypersomnolence Disorder

Symptoms:

  • Excessive sleepiness and sleep attacks
  • A need for frequent naps
  • Difficulty waking from sleep (sleep inertia)
  • Autonomic symptoms such as reduced blood flow to the brain on awakening

Parasomnias

Symptoms:

  • Abnormal behavioral or physiological events associated with sleep
  • Sleepwalking
  • Night terrors
  • Sleep eating
  • REM sleep behavior disorder

Neurocognitive Disorders

Dementia

Symptoms:

  • Memory loss
  • Difficulty communicating
  • Difficulty sequencing tasks
  • Agitation
  • Withdrawal

Major Neurocognitive Disorder (previously known as Dementia)

Symptoms:

  • Significant cognitive decline from a previous level of performance in one or more cognitive domains
  • Interference with independent daily functioning
  • Alzheimer’s disease is the most common cause

Substance-Related and Addictive Disorders

Substance Use Disorders

Symptoms:

  • Taking the substance in larger amounts or for longer than you’re meant to
  • Wanting to cut down or stop using the substance but not managing to
  • Spending a lot of time getting, using, or recovering from the use of the substance
  • Cravings and urges to use the substance

Alcohol-Related Disorders

Symptoms:

  • Inability to control the amount of alcohol consumed
  • Continuing to drink despite negative psychological or physical effects
  • Developing a tolerance for alcohol
  • Experiencing withdrawal symptoms when not drinking

Tobacco-Related Disorders

Symptoms:

  • Needing to smoke more and more to get the same effect
  • Giving up important activities or social events to smoke
  • Experiencing withdrawal symptoms when trying to quit

Personality Disorders

Borderline Personality Disorder (BPD)

Symptoms:

  • Intense fear of abandonment and a series of other emotional relational patterns of behavior
  • Unstable sense of identity
  • Involvement in intense and unstable relationships
  • Impulsive and self-damaging behaviors
  • Suicidal behavior

Antisocial Personality Disorder

Symptoms:

  • Disregard for right and wrong
  • Persistent lying or deceit to exploit others
  • Being callous, cynical, and disrespectful of others
  • Using charm or wit to manipulate others for personal gain or personal pleasure
  • Arrogance, a sense of superiority, and being extremely opinionated

Paranoid Personality Disorder

Symptoms:

  • Distrust and suspicion of others’ motives
  • Belief that others are trying to harm or deceive you
  • Reluctance to confide in others
  • Perception of hidden meanings in innocent remarks
  • Holding grudges and unforgiving of perceived slights or insults

Disruptive, Impulse-Control, and Conduct Disorders

Oppositional Defiant Disorder (ODD)

Symptoms:

  • Angry and irritable mood
  • Argumentative and defiant behavior
  • Vindictiveness
  • Troubled relationships with authority figures

Intermittent Explosive Disorder

Symptoms:

  • Frequent, uncontrollable outbursts of anger
  • Inability to control the aggression
  • Extreme behavior out of proportion to the situation
  • Verbal aggression, physical aggression, or a combination

Conduct Disorder

Symptoms:

  • Aggression to people and animals
  • Destruction of property
  • Deceitfulness or theft
  • Serious violation of rules
  • Often moves into antisocial behavior as an adult

Neurodevelopmental and Learning Disorders

Dyslexia

Symptoms:

  • Difficulty with reading
  • Problems with spelling
  • Difficulty in associating letters with the sounds that they represent
  • Difficulty learning to decode words

Dyscalculia

Symptoms:

  • Difficulty understanding mathematical concepts
  • Trouble performing mathematical operations
  • Struggling to learn math facts
  • Difficulty understanding time, using money, and maintaining a mental map

Dysgraphia

Symptoms:

  • Problems with handwriting
  • Trouble putting thoughts on paper
  • Difficulty with grammar and organization
  • Complicated relationship between writing and spelling difficulties

Attention-Deficit/Hyperactivity Disorder (ADHD)

Symptoms:

  • Inattention and difficulty concentrating
  • Hyperactivity and impulsivity
  • Restlessness and difficulty sitting still
  • Forgetfulness and poor organizational skills
  • Frequent shifting from one uncompleted activity to another

Eating Disorders

Anorexia Nervosa

Symptoms:

  • Restriction of energy intake relative to requirements leading to a significantly low body weight
  • Intense fear of gaining weight or becoming fat
  • Distorted body image, including denial of the severity of low body weight

Bulimia Nervosa

Symptoms:

  • Recurrent episodes of binge eating
  • Eating large amounts of food when not feeling physically hungry
  • Recurrent inappropriate compensatory behaviors to prevent weight gain
  • Self-evaluation predominantly influenced by body shape and weight

Binge-Eating Disorder

Symptoms:

  • Recurrent episodes of binge eating
  • Eating much more rapidly than normal
  • Eating until feeling uncomfortably full
  • Eating large amounts of food when not feeling physically hungry
  • Eating alone because of feeling embarrassed by how much one is eating
  • Feeling disgusted with oneself, depressed, or very guilty afterward

Disruptive, Impulse-Control, and Conduct Disorders

Oppositional Defiant Disorder

Symptoms:

  • Angry and irritable mood
  • Argumentative and defiant behavior
  • Vindictiveness
  • Troubled relationships with authority figures

Intermittent Explosive Disorder

Symptoms:

  • Frequent, uncontrollable outbursts of anger
  • Inability to control the aggression
  • Extreme behavior out of proportion to the situation
  • Verbal aggression, physical aggression, or a combination

Conduct Disorder

Symptoms:

  • Aggression to people and animals
  • Destruction of property
  • Deceitfulness or theft
  • Serious violation of rules
  • Often moves into antisocial behavior as an adult

Neurocognitive Disorders

Dementia

Symptoms:

  • Memory loss
  • Difficulty communicating
  • Difficulty sequencing tasks
  • Agitation
  • Withdrawal

Major Neurocognitive Disorder (previously known as Dementia)

Symptoms:

  • Significant cognitive decline from a previous level of performance in one or more cognitive domains
  • Interference with independent daily functioning
  • Alzheimer’s disease is the most common cause

This exhaustive resource provides an in-depth look at various mental health disorders that affect a significant portion of the population globally. Understanding the symptoms and patterns associated with each condition is a critical step toward deepening our empathy and support for individuals living with mental health challenges. In the evolving landscape of mental wellness, this resource stands as a beacon of reference for all who seek to be better informed and better equipped to make a positive impact.

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