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Psychological disorders

Mood disorders

Major depressive disorder


Bipolar disorder

Seasonal affective disorder

Premenstrual dysphoric disorder

Anxiety disorders

Generalized anxiety disorder

Social anxiety disorder

Panic disorder



Obsessive-compulsive disorders

Obsessive-compulsive disorder

Body focused repetitive disorders

Body dysmorphic disorder

Stress-related disorders and abuse

Post-traumatic stress disorder

Physical and sexual abuse

Psychotic disorders

Schizoaffective disorder

Schizophreniform disorder

Delusional disorder


Cognitive and dissociative disorders



Dissociative disorders

Eating disorders

Anorexia nervosa

Bulimia nervosa

Personality disorders

Cluster A personality disorders

Cluster B personality disorders

Cluster C personality disorders

Somatoform and factitious disorders

Somatic symptom disorder

Factitious disorder

Substance use disorders and drugs of abuse

Tobacco dependence

Opioid dependence

Cannabis dependence

Cocaine dependence

Alcohol use disorder

Sleep disorders


Nocturnal enuresis


Night terrors

Narcolepsy (NORD)

Sexual dysfunction disorders

Erectile dysfunction

Male hypoactive sexual desire disorder

Orgasmic dysfunction

Female sexual interest and arousal disorder

Genito-pelvic pain and penetration disorder

Pediatric disorders

Attention deficit hyperactivity disorder

Disruptive, impulse control, and conduct disorders

Learning disability

Fetal alcohol syndrome

Tourette syndrome

Autism spectrum disorder

Rett syndrome

Shaken baby syndrome



Psychiatric emergencies


Serotonin syndrome

Neuroleptic malignant syndrome

Psychological disorders review

Mood disorders: Pathology review

Amnesia, dissociative disorders and delirium: Pathology review

Personality disorders: Pathology review

Eating disorders: Pathology review

Psychological sleep disorders: Pathology review

Psychiatric emergencies: Pathology review

Drug misuse, intoxication and withdrawal: Hallucinogens: Pathology review

Malingering, factitious disorders and somatoform disorders: Pathology review

Anxiety disorders, phobias and stress-related disorders: Pathology Review

Trauma- and stress-related disorders: Pathology review

Schizophrenia spectrum disorders: Pathology review

Drug misuse, intoxication and withdrawal: Stimulants: Pathology review

Drug misuse, intoxication and withdrawal: Alcohol: Pathology review

Developmental and learning disorders: Pathology review

Childhood and early-onset psychological disorders: Pathology review




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USMLE® Step 1 questions

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High Yield Notes

7 pages



of complete


USMLE® Step 1 style questions USMLE

of complete

A 30-year-old woman comes to the physician because she has become afraid to leave the house. The patient used to take the train to work every day, but she has experienced increasing anxiety about traveling in an enclosed space surrounded by people. Seven months ago, the patient had a panic attack in a public train station, and she reports feeling “terrified that might happen again.” Ever since that episode, the patient has avoided using public transportation, and she requested to work her job fully remote so that she no longer needs to leave her home. She has also started to avoid other public places where large crowds may be present, which has resulted in her no longer attending her place of worship. She states that she feels safe if she “just stays in the house.” She was diagnosed with major depressive disorder five years ago and was treated successfully with sertraline. She no longer takes any medications. Which of the following is the most likely diagnosis in this patient?

External References

First Aid




Benzodiazepines p. 529

phobias p. 547

β -blockers p. 241

phobias p. 547

Cognitive behavioral therapy (CBT) p. 541

phobias p. 547

MAO inhibitors p. 559

phobias p. 547

Phobias p. 546, 547

SSRIs (selective serotonin reuptake inhibitors) p. 559

phobias p. 547

Venlafaxine p. 559

phobias p. 547

External Links


Content Reviewers

Rishi Desai, MD, MPH


Tanner Marshall, MS

Everybody, whether they like to admit it or not, has fears and gets anxious about certain things, whether it be a spider crawling on the ground or speaking in front of large groups of people.

In most cases though, people cope with those fears and confront them.

A phobia is the most extreme type of fear.

Someone with a phobia will go to great lengths to avoid being exposed to the fear or perceived danger, even if there’s no actual risk or danger, and people often feel powerless against it.

Phobias are considered the most common psychiatric disorder, affecting almost 10% of the population.

Phobias are extreme, often unreasonable and irrational fears of something, which could literally be anything, like: pyrophobia, the fear of fire; alektorophobia, the fear of chickens; triskaidekaphobia, the fear of the number 13; phobophobia, the fear of developing phobias; or even pinaciphobia, the fear of lists.

Unreasonable or irrational fears get in the way of daily routines, work, and relationships, because patients with phobias often do whatever they can to avoid the anxiety and terrifying feelings associated with the phobia.

For example, most people don’t necessarily enjoy the company of spiders, but they also don’t let this fear affect their social or daily life; like, even though I know there are spiders in the woods, I wouldn’t avoid a camping trip on account of the spiders.

Even if they love camping, somebody with arachnophobia—a fear of spiders—might refuse to go because they know there’s a possibility of seeing a spider in close quarters.

In this case the fear’s clearly interfering with their social life and relationship with friends, meaning it’s a phobia.

An irrational fear of an object or situation like this is called a specific phobia.

The DSM-5 splits these specific phobias into five categories: fear of animals, like arachnophobia or alektorophobia; fear of the natural environment, like thalassophobia (fear of the ocean) or nyctophobia (fear of darkness); fear of blood and needles, like hemophobia (fear of blood); situational fears like aviophobia (fear of flying); and finally, “other” fears, like coulrophobia (fear of clowns).

These specific phobias are one of three main types of phobias.


Phobias are extreme, often irrational fears that interfere with a person's ability to function in their daily lives. Such fears are typically associated with a specific object, situation, or activity. Particularly bad phobias can cause physical symptoms like sweating, trembling, and increases in heart rate. Common phobias include fear of heights (acrophobia), fear of closed-in spaces (claustrophobia), fear of flying (aviophobia), fear of animals (zoophobia), and fear of social situations (social phobia). Managing phobias can require psychotherapy, particularly cognitive-behavioral therapy


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  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "Diagnostic and Statistical Manual of Mental Disorders (DSM-5 )" American Psychiatric Assoc Pub (2013)
  5. "Mechanisms of fear extinction" Molecular Psychiatry (2006)
  6. "Why do some individuals develop social phobia? A review with emphasis on the neurobiological influences" Nordic Journal of Psychiatry (2004)

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