Major depressive disorder


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Major depressive disorder

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


Major depressive disorder


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High Yield Notes

5 pages


Major depressive disorder

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External References

First Aid








Cognitive behavioral therapy (CBT) p. 580

postpartum depression p. 585

Postpartum depression p. 585

SSRIs (selective serotonin reuptake inhibitors) p. 599

postpartum depression p. 585


Content Reviewers

Rishi Desai, MD, MPH


Tanner Marshall, MS

Clinical depression, which is sometimes called major depressive disorder or unipolar depression, is a serious mental disorder characterized by by persistent sadness and a loss of interest in the activities of daily life, like working, studying, participating in hobbies, eating, and sleeping.

Clinical depression has a lifetime incidence of up to 20% in women and 12% in men, making it one of the most common reasons people seek out mental health services.

In addition to being relatively common, clinical depression is very serious because it essentially leads to an overall feeling that life isn’t enjoyable.

We don’t exactly know what specifically causes clinical depression, but it’s probably the result of a combination of genetic factors, biological factors, environmental factors, and psychological factors.

It’s been shown that people with family members who have depression are three times more likely to have it themselves, especially if they’re closely related.

Medications that address the biological factors of depression focus specifically on neurotransmitters.

Neurotransmitters are signaling molecules in the brain that are released by one neuron and received by the receptors of another neuron.

Through this process, a message is transmitted from one neuron to the next.

The body’s ability to regulate how many of these neurotransmitters are sent between neurons at any given time is thought to play an important role in the development of depression’s symptoms.

That’s because neurotransmitters are likely involved in regulating a lot of brain functions, including mood, attention, sleep, appetite, and cognition.

The three main neurotransmitters that treatment for depression focuses on are serotonin, norepinephrine, and dopamine.

That’s because medications that increase the amount of these neurotransmitters in the synaptic cleft — this space between the neurons — are shown to be effective antidepressants.


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