Anxiety disorders include panic disorder (PD), generalized anxiety disorder (GAD), social anxiety disorder (SAD), and specific phobic disorders. Until the publication of the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5), obsessive-compulsive disorder (OCD) and post-traumatic stress disorder (PTSD) were classified as anxiety disorders. Now, OCD and PTSD are classified separately from anxiety disorders; however, they will be discussed in this chapter due to significant overlap in medications used to treat these disorders. Specific phobias will not be addressed in this chapter, because pharmacotherapy has only a limited role in phobia treatment. For patients to be diagnosed with an anxiety disorder, the symptoms must cause significant impairment in social or occupational functioning and cannot be due to a general medical condition or substance.
PD is characterized by recurrent unexpected panic attacks with associated anticipatory anxiety for at least 1 month. PD may be associated with agoraphobia, which is the fear of being in a place or situation where escape may be difficult. A panic attack is a discrete period of fear or discomfort, and characterized by somatic or cognitive symptoms such as chest pain, palpitations, sweating, shortness of breath, fear of dying, dizziness, or hot flashes. These symptoms appear suddenly and last about 10 minutes. Patients can have multiple panic attacks in their lifetime; therefore, panic attacks alone do not constitute a diagnosis of PD.
Generalized Anxiety Disorder
GAD is characterized by chronic excessive worry and anxiety about life events, difficulty controlling the worry, and lasting at least 6 months. Additional symptoms include feeling restless, difficulty concentrating, muscle tension, sleep disturbance, and being easily fatigued. A high incidence of comorbidity exists with major depressive disorder.
Patients with OCD have either obsessions, compulsions, or both. Obsessions are marked by recurrent and persistent thoughts that are intrusive and cause significant anxiety. Compulsions are characterized by repetitive behaviors that a person feels driven to perform to reduce anxiety. Adults who have either obsessions or compulsions recognize that these feelings are excessive, but they are unable to control these thoughts or actions. To meet criteria for a diagnosis of OCD, the symptoms must cause significant distress and must be time consuming (>1 h/d).
Post-traumatic Stress Disorder
PTSD is characterized by symptoms that occur after exposure to a traumatic event such as military combat or violent personal attack. Symptoms must be present for at least 1 month and include the following types of indicators: re-experiencing (flashbacks, dreams), avoidance (of activities or people associated with the trauma), and increased arousal (sleep disturbance, exaggerated startle response). Comorbidity with another psychiatric illness such as major depressive disorder is common among patients with PTSD. Most symptoms of PTSD occur within 3 months of exposure to the trauma, but they can appear ...