Anxiety disorders

Last updated: December 5, 2023

Summarytoggle arrow icon

Anxiety disorders cover a broad spectrum of conditions characterized by excessive and persistent fear (an emotional response to imminent threats), anxiety (the anticipation of a future threat), worry (apprehensive expectation), and/or avoidance behavior. The etiology of anxiety disorders is multifactorial and may involve genetic, developmental, environmental, neurobiological, cognitive, and psychosocial factors. Therapy typically consists of a combination of pharmacotherapy, especially selective serotonin reuptake inhibitors (SSRIs), and psychotherapy, especially cognitive behavioral therapy (CBT).

Overviewtoggle arrow icon

Overview of the most important anxiety disorders
Characteristics Generalized anxiety disorder (GAD) Panic disorder Social anxiety disorder (SAD) Specific phobias Agoraphobia Substance/medication-induced anxiety disorder

Clinical features

  • Prolonged and excessive anxiety not focused on a single specific fear
  • Pronounced anxiety of social situations that involve scrutiny from others
  • Persistent and intense fears of particular situations or objects
  • Pronounced fear or anxiety of situations that are perceived as difficult to escape from
  • Prominent anxiety or panic attacks after using or stopping a substance/medication
  • No definitive trigger or source
  • May not have an obvious trigger
  • Social interaction and/or performance of any actions in public
  • One or more specific situations or objects
  • Being in enclosed spaces or open public spaces
  • Crowds
  • Being alone
Duration of symptoms required for diagnosis
  • ≥ 6 months
  • Panic attacks: several minutes
  • Fear of subsequent attacks: ≥ 1 month
  • ≥ 6 months
  • ≥ 6 months
  • ≥ 6 months in ≥ 2 different situations
  • Within 1 month of using or stopping the substance/medication
Treatment of anxiety disorders

Etiologytoggle arrow icon

Generalized anxiety disordertoggle arrow icon

  • Definition: an anxiety disorder in which patients have anxiety that is prolonged, excessive, persistent (> 6 months), and caused by various aspects of daily life instead of a single specific situation or object
  • Epidemiology [1]
    • Most common anxiety disorder among the elderly population
    • Lifetime prevalence: 5–10%
    • > (2:1)
  • Clinical features: diagnosis is confirmed if the following symptoms occur more days than not for at least 6 months (≥ 1 symptom in children, ≥ 3 in adults)
    • Nervousness, restlessness
    • Irritability
    • Muscle tension
    • Somnolence, fatigue
    • Concentration difficulties
    • Insomnia
  • Differential diagnosis
  • Treatment [2]
  • Special patient groups: perinatal generalized anxiety disorder
    • Definition: generalized anxiety that occurs from pregnancy through one year postpartum
    • Epidemiology: Prevalence during pregnancy is ∼ 10%. [4]
    • Risk factors
    • Clinical features
      • Disproportionate, overwhelming fears about fetal and/or paternal well-being (e.g., excessive concerns about baby's health)
      • Functional impairment, such as inability to work (in moderate to severe anxiety)
      • Physical symptoms (e.g., fatigue, insomnia, muscle tension)
    • Treatment
      • Psychotherapy for mild symptoms
      • Psychotherapy and/or pharmacotherapy (e.g., SSRIs, SNRIs) for moderate to severe anxiety
      • Treatment is required if symptoms cause functional impairment.

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Acute panic attacktoggle arrow icon


An abrupt episode of intense fear associated with physical and cognitive symptoms [6][7]

Etiology [6][8]

Clinical features [8]

Acute panic attacks peak within several minutes and involve ≥ 4 of the following cognitive and/or somatic symptoms:

STUDENTS FEAR the 3Cs:” Sweating, Trembling, Unsteadiness (dizziness), Derealization, Elevated heart rate (palpitations), Nausea, Tingling, and Shortness of breath; FEAR of dying or going crazy; Chest pain, Choking, and Chills.


Differential diagnosis

Consider the following based on the presenting clinical feature:

Management of acute panic attack [9][10]

Panic attacks typically self-resolve within 30 minutes of onset and may not require acute intervention. [9]

Panic disordertoggle arrow icon

Social anxiety disordertoggle arrow icon

  • Definition: pronounced anxiety lasting ≥ 6 months of social situations that might involve scrutiny by others
  • Epidemiology
  • Types
    • Social anxiety disorder (SAD): fear/anxiety out of proportion to a social situation where one may be scrutinized by others (e.g., meeting new people at a party, eating in public)
    • Performance-only SAD: symptoms of fear/anxiety restricted only to public speaking or performing in front of crowds
    • Paruresis (shy bladder syndrome): fear/anxiety associated with urinating when other people are present, e.g., in public restrooms
  • Clinical features
    • Blushing, palpitations, sweating during a social interaction
    • Anticipatory anxiety (e.g., worrying weeks in advance about attending a social event)
    • Anxiety driven by fear of embarrassment and others noticing the reaction
    • Avoidance of the aforementioned triggers (e.g., not attending parties, refusing to attend school)
    • In children: refusing to speak at social events, crying/throwing a tantrum, clinging to their caregiver
  • Treatment


Specific phobiastoggle arrow icon

  • Definition
    • Persistent (≥ 6 months) and intense fears of one or more specific situations or objects (phobic stimuli)
    • Always occurs during encounters with the phobic stimulus but may already surge in anticipation of an encounter
  • Epidemiology
    • Lifetime prevalence: up to 10% of the population [15]
    • The average age of onset depends on the specific phobia (e.g., animal phobias more commonly develop in early childhood).
    • > (2:1)
  • Common phobias
    • Animal: spiders (arachnophobia), insects (entomophobia), dogs (cynophobia)
    • Natural environment: heights (acrophobia), storms (astraphobia)
    • Blood-injection-injury: blood (hematophobia), needles (belonephobia), dental procedures (odontophobia), fear of injury (traumatophobia)
    • Situational: enclosed places (claustrophobia), flying (aviophobia)
    • Other: fear of vomiting (emetophobia), the number 13 (triskaidekaphobia), costumed characters (masklophobia), fear of clowns (coulrophobia)
  • Treatment

Agoraphobiatoggle arrow icon

  • Definition: pronounced fear or anxiety of being in situations that are perceived as difficult to escape from or situations in which it might be difficult to seek help
  • Epidemiology
    • > (2:1)
    • Age of onset: < 35 years (60–70% of cases)
  • Clinical features
    • Fear, anxiety, or even panic attacks over a period of ≥ 6 months in ≥ 2 of the following 5 situations:
      • Using public transportation
      • Being in open spaces
      • Being in enclosed places
      • Standing in line or being in a crowd
      • Being outside of the home alone
    • Active avoidance of these settings unless a companion is present
    • Fear can become so severe that the affected individual feels unable to leave the house.
    • Some patients can have comorbid panic disorder.
  • Treatment

If a patient meets the criteria for panic disorder and agoraphobia, both conditions should be diagnosed.


Hyperventilation syndrometoggle arrow icon

Background [19][20][21]

Clinical features [23]

Diagnosis [23][24]

Hyperventilation syndrome is a diagnosis of exclusion.

Differential diagnosis

See also “Differential diagnosis of dyspnea.”

Acute management [23]

Rebreathing into a paper bag can cause significant hypoxemia and is therefore not recommended. [25]

Abnormal findings on physical exam (e.g., jugular venous distention, wheezing, crackles, altered mental status) suggest a diagnosis other than hyperventilation syndrome.

Substance/medication-induced anxiety disordertoggle arrow icon

Anxiety due to another medical conditiontoggle arrow icon

Patients should be evaluated for medical conditions that can cause anxiety. Anxiety due to another medical condition is diagnosed if the condition was diagnosed before the onset of anxiety. Possible underlying conditions include:

Separation anxiety disordertoggle arrow icon

  • Description: : a disorder characterized by excessive fear, anxiety, or avoidance of separation from major attachment figures
    • Separation anxiety disorder differs from nonpathological separation anxiety in its intensity and effect on the social and academic life of the individual.
    • Separation anxiety is normal in children under a developmental age of 3 years. [30]
    • Typically develops after a stressful life event, usually involving some form of loss (e.g., death of a relative, parental divorce, change of school)
    • Onset: the condition can occur in, or persist into, adulthood and may have a debilitating effect on an individual's ability to work or socialize in the absence of attachment figures.
  • Diagnostic criteria (DSM-V) [5]
    • Fear of separation from major attachment figures, that is excessive for developmental level, involving at least 3 of the following features:
      • Recurrent and excessive distress prior to, or during, separation
      • Persistent worrying about the loss of attachment figures (e.g., due to illness, injury, or death)
      • Persistent worrying about separation due to the individual being lost, kidnapped, injured, or ill
      • Persistent reluctant to leave home due to fear of separation
      • Avoidance of being left alone (e.g., at home or elsewhere)
      • Avoidance of falling asleep, or sleeping away from home, without major attachment figure
      • Persistent nightmares about separation
      • Persistent somatic symptoms (e.g., headaches, nausea/vomiting, abdominal pain)
    • Duration: symptoms persist for at least 4 weeks in children/adolescents and 6 months in adults
    • Significant impairment of academic, social, and/or work life (e.g., often a precursor to school refusal)
    • Symptoms are not attributable to another psychiatric disorder (e.g., autism spectrum disorder, psychosis, other anxiety disorders).

Children under 3 years of age commonly undergo periods of separation anxiety from attachment figures as a normal part of their development. The diagnosis of separation anxiety disorder should only be considered if the symptoms become excessive for developmental level. [30]

Selective mutismtoggle arrow icon

  • Description: a psychiatric disorder characterized by the inability to speak in specific social situations (e.g., during class)
    • Typically normal development of language and speech.
    • Onset: generally before 5 years of age, although may not become clinically relevant until the child is required to perform verbally (e.g., with the start of school)
  • Diagnostic criteria (DSM-V) [5]
    • Consistent inability to speak in specific social settings where speaking is expected (e.g., does not speak in class but speaks at home)
    • Interferes with academic or professional performance and social interaction
    • Duration of symptoms: at least 1 month
    • The inability to speak is not due to difficulties or discomfort with the spoken language expected in the social situation.
    • The inability to speak is not attributable to schizophrenia spectrum disorder or another psychotic disorder, autism spectrum disorder, or a communication disorder.
  • Treatment [32]
  • Complications: may coexist with social anxiety disorder and may also result in school refusal

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Referencestoggle arrow icon

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