Anxiety disorders

Last updated: March 23, 2022

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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).

For separation anxiety disorder and selective mutism, see the article on “Emotional and behavioral disorders in children and adolescents.”

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

  • Definition: prolonged and excessive anxiety that:
    • Is not focused on a single specific fear but may revolve around certain themes (e.g., health, work)
    • Causes clinically significant distress
    • Is not caused by substance use, medication, or underlying medical condition
  • 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]

Don't get anxious if the BUS doesn’t arrive at ONE; just take a BUSpirONE.


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.

  • 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


  • 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 [9]
    • 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 (blenophobia), 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

  • 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.



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:

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