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For further information, see CMDT Part 25-05: Anxiety Disorders

Key Features

Essentials of Diagnosis

  • Persistent excessive anxiety or chronic fear and associated behavioral disturbances

    • Somatic symptoms referable to the autonomic nervous system or to a specific organ system (eg, dyspnea, palpitations, paresthesias)

    • Not limited to an adjustment disorder

  • Not a result of physical disorders (eg, hyperthyroidism), other psychiatric conditions (eg, schizophrenia), or drug abuse

General Considerations

  • Anxiety can become self-generating, since the symptoms reinforce the reaction, causing it to spiral

  • Additionally, avoidance of triggers of anxiety leads to reinforcement of the anxiety, because the person never relearns through experience that the trigger need not always result in fear, or that anxiety will naturally improve with prolonged exposure to an objectively neutral stressor

  • Anxiety disorders include

    • Generalized anxiety disorder (GAD)

    • Panic disorder

    • Phobic disorder

  • GAD

    • Everyday activities trigger symptoms

    • Symptoms present on most days for at least 6 months

  • Panic disorder

    • Symptoms occur in recurrent episodes with unpredictable triggers

    • Somatic symptoms are often marked

  • Phobic disorder

    • Symptoms occur predictably

    • Follows exposure to certain objects or situations


  • About 7% of women and 4% of men will meet criteria for GAD over a lifetime

  • GAD becomes chronic in many patients, lasting longer than 2 years in > 50%

  • Anxiety disorder in the elderly is twice as common as dementia and 4–6 times more common than major depression

  • Prevalence of panic disorder: 3–5%, 25% with coincident obsessive-compulsive disorder

Clinical Findings

Symptoms and Signs

  • The principal components of anxiety are psychological and somatic

    • Psychological

      • Tension

      • Recurrent thoughts or fears

      • Apprehension or worry

      • Difficulty concentrating

      • Irritability

      • Feelings of impending doom

    • Somatic

      • Chest pain

      • Tachycardia

      • Hyperventilation

      • Shortness of breath

      • Palpitations

      • Tremor

      • Sweating

      • Paresthesias

      • Nausea

      • Dizziness

  • Other organ systems (eg, gastrointestinal) may be involved

  • Fatigue and sleep disturbances are common

  • Sympathomimetic symptoms (eg, tachycardia, hyperventilation, tremor, sweating) are both a response to CNS state and a reinforcement of further anxiety

  • Repetitive actions and rituals

  • Avoidant behaviors

Differential Diagnosis

  • Hyperthyroidism

  • Pheochromocytoma

  • Sympathomimetic drug use

  • Myocardial infarction

  • Hypoglycemia

  • Adjustment disorder


Laboratory Tests

  • Serum thyroid-stimulating hormone

  • Complete blood count

  • Toxicology screen (if drug abuse is suspected)

  • Blood glucose

Imaging Studies

  • Chest radiograph may be indicated

  • Head CT may be useful in dissociative symptoms to rule out temporal lobe lesion

Diagnostic Procedures

  • ECG

  • Electroencephalogram may be useful in dissociative symptoms to rule out temporal lobe lesion



  • See Table 25–1

  • GAD

    • Antidepressants (including the SSRIs and SNRIs) are safe and effective; they appear to be ...

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