Anxiety, Obsessive-Compulsive & Trauma-Related Disorders

Generalized Anxiety and Panic

Generalized anxiety disorder (GAD). Excessive, hard-to-control worry about many everyday matters on more days than not for ≥6 months, with ≥3 of restlessness, fatigue, poor concentration, irritability, muscle tension, and sleep disturbance (only 1 is needed in children). There are no discrete attacks. First-line treatment is CBT plus an SSRI or SNRI; benzodiazepines are for short-term use only. Buspirone, a 5-HT_1A partial agonist, treats GAD without sedation or dependence, but it takes weeks to work and does not help panic.

Panic attack. An abrupt surge of intense fear that peaks within minutes, with ≥4 symptoms: palpitations, sweating, trembling, dyspnea, choking, chest pain, nausea, dizziness, chills or heat, paresthesias, derealization, and fear of losing control or dying. Panic disorder requires recurrent UNEXPECTED attacks plus ≥1 month of worry about more attacks or maladaptive avoidance, such as giving up driving.

Medical mimics. Before diagnosing panic disorder, exclude hyperthyroidism (TSH); pheochromocytoma (episodic hypertension, headache, sweating; plasma metanephrines); stimulant intoxication (cocaine, amphetamines, caffeine); alcohol or benzodiazepine withdrawal; arrhythmia such as SVT (ECG); hypoglycemia; and cardiopulmonary causes (MI, asthma, PE).

Neurobiology and treatment of panic. Panic involves an amygdala-centered fear circuit with noradrenergic hyperactivity of the locus coeruleus. CO₂ inhalation or lactate infusion can provoke attacks, and one model casts panic as a false suffocation alarm set off by CO₂ hypersensitivity, which explains the prominent dyspnea. CBT plus an SSRI or SNRI prevents attacks. Benzodiazepines serve only as a short bridge, because they cause dependence and their withdrawal can itself trigger panic.

Phobic and Childhood Anxiety Disorders

Agoraphobia. Fear or avoidance of ≥2 of 5 situation types (public transport, open spaces, enclosed places such as stores or theaters, lines or crowds, being outside the home alone) because escape might be difficult or help unavailable if panic-like symptoms strike, lasting ≥6 months. It is diagnosed independently of panic disorder, though the two often coexist.

Specific phobia. Marked, out-of-proportion fear of a particular object or situation (animals, heights, flying, blood or needles), avoided or endured with intense anxiety for ≥6 months. Exposure-based CBT such as systematic desensitization is the treatment. Blood-injection-injury phobia uniquely causes vasovagal fainting: a brief rise in heart rate and blood pressure, then bradycardia and hypotension.

Social anxiety disorder. Fear of being judged or embarrassed in social or performance situations, avoided or endured with dread, for ≥6 months. Treat with CBT plus an SSRI or SNRI (venlafaxine). In the performance-only type (public speaking, recitals), a β-blocker such as propranolol taken beforehand blunts tremor and tachycardia.

Separation anxiety disorder. Developmentally excessive fear of separation from attachment figures, with school refusal, nightmares, somatic complaints, and fear that harm will befall the parents, lasting ≥4 weeks in children (usually ≥6 months in adults).

Selective mutism. Consistent failure to speak in specific settings such as school despite normal speech at home, for ≥1 month (not just the first month of school), with normal hearing and language. It is strongly linked to social anxiety.

Obsessive-Compulsive and Related Disorders

OCD. Intrusive, unwanted obsessions (contamination, harm, symmetry, taboo thoughts) cause anxiety that compulsions (washing, checking, counting, mental rituals) temporarily relieve. Symptoms are time-consuming (>1 hour/day) or impairing. OCD is ego-dystonic: most patients recognize the thoughts as excessive, and insight is specified as good, poor, or absent.

Circuitry and associations. Imaging shows hyperactivity in the cortico-striato-thalamo-cortical circuit: orbitofrontal cortex, anterior cingulate, and caudate. OCD clusters with Tourette syndrome and tic disorders. Abrupt childhood onset after group A streptococcal infection suggests PANDAS, attributed to antibodies cross-reacting with the basal ganglia, as in Sydenham chorea.

Treatment. First-line therapy is exposure and response prevention (face the trigger, withhold the ritual), which works because each ritual's relief is negative reinforcement. SSRIs are used at higher doses and for longer trials (8–12 weeks) than for depression. Clomipramine, the most serotonergic TCA, works but is less tolerated (anticholinergic effects, QT prolongation, seizures). Refractory cases add an antipsychotic (risperidone, aripiprazole).

OCD is ego-dystonic with true obsessions and compulsions; obsessive-compulsive personality disorder is ego-syntonic perfectionism and rigidity without them.

• Body dysmorphic disorder: preoccupation with a slight or imagined appearance flaw plus mirror checking, grooming, or reassurance seeking, even when insight is absent. Cosmetic surgery rarely helps; use an SSRI plus CBT.
• Hoarding disorder: persistent difficulty discarding possessions, leading to clutter, often with poor insight.
• Trichotillomania: hair pulling with patchy hair loss; broken hairs of varying lengths distinguish it from alopecia areata, and swallowed hair (trichophagia) can form a gastric trichobezoar.
• Excoriation disorder: skin picking with lesions. It and trichotillomania respond to habit reversal training.

Trauma- and Stressor-Related Disorders

Timing defines the diagnosis. After a traumatic event, symptoms lasting under 3 days are a transient acute stress reaction, symptoms lasting 3 days to 1 month are acute stress disorder, and symptoms lasting more than 1 month are PTSD (with delayed expression if full criteria appear ≥6 months later). Adjustment disorder follows any identifiable stressor, such as divorce or job loss, within 3 months, is disproportionate or impairing without meeting criteria for another disorder, and resolves within 6 months after the stressor or its consequences end.

PTSD. Follows actual or threatened death, serious injury, or sexual violence that is experienced, witnessed, learned of for a loved one, or encountered repeatedly at work. The four symptom clusters are intrusions (flashbacks, nightmares), avoidance, negative cognition and mood (self-blame, detachment, amnesia), and hyperarousal (hypervigilance, exaggerated startle, insomnia). Neurobiology includes a hyperactive amygdala, hypoactive medial prefrontal cortex, smaller hippocampus, and increased norepinephrine. Unlike the hypercortisolism of depression, PTSD often shows low-normal cortisol with exaggerated dexamethasone suppression.

PTSD treatment. Trauma-focused psychotherapy (cognitive processing therapy, prolonged exposure, EMDR) is first-line, with SSRIs (sertraline, paroxetine) or venlafaxine. The α1-blocker prazosin reduces trauma nightmares by dampening central noradrenergic arousal.

Avoid benzodiazepines in PTSD: they neither prevent nor treat it and may worsen outcomes.