Phobic Disorders Treatment & Management
- Author: Adrian Preda, MD; Chief Editor: Iqbal Ahmed, MBBS, FRCPsych(UK) more...
Anxiety often is not a significantly pathologic condition but simply a physiologic reaction that can be expected to occur under stressful life circumstances. Most anxiety reactions do not result in dysfunction or disability and will remit spontaneously over time. In addition, high placebo response rates have been documented across a range of anxiety disorders. Accordingly, when an anxiety disorder is mild (ie, not associated with disability), a wait-and-see, supportive type of intervention is recommended.
Treatment of phobic disorders usually consists of pharmacotherapy, psychotherapy, or some combination thereof. As a general rule, a selected medication regimen should be continued for at least 6-12 months. If the symptoms have resolved and the patient is not experiencing excessive stress, the physician can gradually taper the patient off the medication. Psychotherapy usually helps make the transition away from medication more successful.
Social anxiety disorder (social phobia)
At present, 3 drugs are approved by the US Food and Drug Administration (FDA) for the treatment of social anxiety disorder, as follows:
The selective serotonin reuptake inhibitors (SSRIs) paroxetine and sertraline
The selective serotonin/norepinephrine reuptake inhibitor (SNRI) venlafaxine
In addition, placebo-controlled, randomized controlled trials and systematic reviews show that social anxiety disorder responds to the following agents:
The SSRIs escitalopram, [39, 40] fluoxetine, and fluvoxamine
The monoamine oxidase inhibitor (MAOI) phenelzine
The reversible inhibitor of monoamine oxidase A (RIMA) moclobemide (not approved in the United States) 
Overall, SSRIs appear to be more effective than MAOIs for the treatment of social anxiety disorder. SSRIs and venlafaxine are generally considered first-line agents, whereas benzodiazepines, tricyclic antidepressants (TCAs), and MAOIs are considered second-line agents.[42, 43] MAOIs and TCAs are not commonly used in this setting. Although both are effective, the former carry a risk of drug-to-drug and dietary interactions, and the latter have tolerability issues.
Antihypertensive beta-blocker therapy can be used as an augmentation strategy. Propranolol may be useful for the circumscribed treatment of situational/performance anxiety on an as-needed basis.
Selected anticonvulsants (eg, gabapentin, pregabalin, valproic acid, topiramate, and tiagabine) have been shown to be effective for social anxiety disorder in mostly open-label, uncontrolled clinical trials. The evidence regarding the serotonin 1 (5HT-1) agonist buspirone in this setting is conflicting. A few other medications, including the second-generation antipsychotics levetiracetam and D-cycloserine, have been considered, but at present, the evidence is insufficient evidence to permit any clear recommendations.[42, 43]
Treatment of social anxiety disorder should be initiated with an SSRI, titrated to the minimum effective dosage. If the response is partial or nonexistent at 6 weeks, the dosage may be increased; this may be done every 2 weeks until the maximum dose is reached.
Patients in whom SSRI therapy fails will sometimes respond to treatment with a high-potency benzodiazepine (eg, clonazepam), an alpha-2-delta calcium channel blocker (eg, gabapentin or pregabalin), the antiepileptic levetiracetam, or the antipsychotic olanzapine; they may also respond to combined SSRI-benzodiazepine therapy.[37, 44, 45]
Buspirone, the beta-blocker atenolol, and the TCA imipramine are all of unproven efficacy in this setting.
Long-term treatment data from double-blind, randomized controlled trials addressing social anxiety disorder show that continuing SSRI or venlafaxine therapy for up to 6 months can result in increased treatment response rates. Long-term treatment data on clonazepam are limited but support the long-term efficacy of this drug.[37, 44, 46]
Beta-blockers, clonidine, and buspirone usually are not helpful for long-term treatment of social anxiety disorder. After 6-12 months of full response, slow tapering of pharmacotherapy should be considered. If symptoms recur after tapering, therapy should be restarted and continued indefinitely.
To date, no controlled studies have demonstrated the efficacy of psychopharmacologic intervention for specific phobias. Clinical lore suggests that as-needed administration of a short-acting benzodiazepine might be useful for temporary anxiety relief in specific situations (eg, right before boarding a plane, for patients with a fear of flying).
Randomized, double-blind, placebo-controlled trials have shown that agoraphobia, specifically the panic symptoms, responds to treatment with SSRIs (eg, escitalopram, citalopram, fluoxetine, fluvoxamine, paroxetine, and sertraline),[47, 48, 49] venlafaxine and reboxetine, some TCAs (eg, clomipramine and imipramine), and some benzodiazepines (eg, alprazolam, lorazepam, diazepam, and clonazepam). Data from comparator-controlled trials suggest that mirtazapine and moclobemide are reasonable alternatives.
Treatment for agoraphobia should be started with an SSRI at a low dosage, which is then titrated to the minimum dosage that effectively controls the patient’s panic. Benzodiazepines can be used either as an adjunct or as primary treatment; however, they are usually not chosen as first-line therapy because of the potential for abuse. If the patient has frequent panic attacks and no history of substance abuse, a benzodiazepine may be considered until the SSRI takes effect.
If the response is minimal or nonexistent after 6 weeks, the SSRI dosage may be further increased every 2 weeks until a response is achieved or the maximal dosage reached. If the response is partial or absent at the highest SSRI dosage, the following alternatives should be considered:
Switch to a different SSRI
Switch to an agent from a different drug class (eg, venlafaxine, reboxetine, or a TCA
Long-acting benzodiazepines (eg, diazepam and clonazepam) prescribed on a standing rather than an as-needed basis are preferred because of the reduced addictive potential; the dosage can be increased every 2-3 days until either the panic symptoms are controlled or the maximum dosage is reached. The short-acting agent alprazolam may be considered for short-term use to control acute symptoms of panic.
Agents with unproven efficacy in this setting include buspirone, propranolol, antihistaminic drugs, and antipsychotic agents.
Double-blind studies show that continuing an SSRI or clomipramine from 12 to 52 weeks results in increased treatment response rates. For a patient with good response, treatment should be continued for 9-12 months before slow tapering of the medications is considered. If symptoms recur after tapering, treatment should be resumed and continued indefinitely.
Pediatric, adolescent, and young adult suicidality
Suicide risk must always be considered, particularly in the treatment of a child or adolescent with a mood disorder. Physicians are advised to be aware of the following information and use appropriate caution when considering treatment with SSRIs in the pediatric and geriatric populations.
In October 2003, the FDA issued a public health advisory regarding reports of suicidality in pediatric patients being treated with antidepressant medications for major depressive disorder. This advisory reported suicidality (both ideation and attempts) in clinical trials of various antidepressant drugs in pediatric patients. The FDA asked that additional studies be performed, because suicidality occurred in both treated and untreated patients with major depression and thus could not be definitively linked to drug treatment.
In December 2003, the UK Medicines and Healthcare Products Regulatory Agency (MHRA) issued an advisory stating that most SSRIs are not suitable for use by persons younger than 18 years for treatment of “depressive illness.” After review, the MHRA decided that the risks that SSRI therapy posed to pediatric patients outweighed the benefits, except in the case of fluoxetine, which appeared to have a positive risk-benefit ratio in the treatment of depressive illness in patients younger than 18 years.
Controlled studies have found behavioral therapy and cognitive behavioral therapy (CBT) to be effective in treating phobic disorders. Computerized CBT (FearFighter) has been recommended for panic and phobia by the National Institute for Health and Clinical Excellence guidelines (NICE).
Psychodynamic therapy (or insight-oriented therapy) is rarely indicated as an exclusive treatment for phobias and is now mostly reserved for cases of phobic disorders that overlap personality disorders. Deciding which treatment or combination of treatments to prescribe depends on a careful interview and assessment of the patient’s goals and level of pathology.
Social anxiety disorder (social phobia)
For treatment of social anxiety disorder, self-exposure monotherapy has been shown to work as well as computer-based exposure training, clinician-led exposure, or combination therapies of self-exposure and CBT/self-help manual. In a small, 12-week randomized trial, school-based training combining exposure therapy and social skills training was highly effective for adolescents aged 14-16 years with social anxiety disorder.[54, 55]
A CBT-based approach, including gradual desensitization, is the most commonly used treatment for specific phobia. Other treatments include relaxation and breathing control techniques.
Randomized controlled clinical trials indicate that specific phobias respond to exposure therapy. A small, randomized controlled clinical trial showed that virtual reality exposure therapy is as effective as standard exposure for treating fear of flying, with gains maintained for up to 1 year after treatment.
In one study, after the successful completion of a 4-session CBT course, patients with specific phobias no longer showed significant functional magnetic resonance imaging (fMRI) activation in the prefrontal or parahippocampal areas ; this finding supports the view that effective psychotherapy can normalize dysfunction in the neurocircuitry associated with anxiety and phobias.
In another study, a single 4-hour CBT session, combined in vivo exposure, and modeling resulted in increased/improved medial orbitofrontal cortex activity and decreased/improved activation in the amygdala and the insula patients with specific phobias as compared with untreated control subjects.
A 2010 meta-analysis showed that a combination of exposure therapy, relaxation, and breathing retraining worked better than other psychological interventions for panic disorder with and without agoraphobia. Furthermore, the inclusion of homework and a follow-up program have been shown to improve outcomes. Early intervention is recommended on the grounds that the shorter the duration of illness is, the better the response will be.
Diet and Activity
The patient’s intake of caffeine (eg, in coffee, caffeinated teas, or sodas) should be assessed; even moderate amounts of caffeine may exacerbate the anxiety response and symptoms. In a small, double-blind, placebo-controlled study, a tryptophan-rich diet was shown to have a positive effect on social anxiety disorder. Dietary restrictions (a tyramine-free diet) are necessary for patients taking MAOIs.
Activity should not be restricted. Patients should be encouraged to confront anxiety-producing stimuli in the context of a behavioral therapy treatment plan.
Overwhelming exposure in early childhood (eg, a frightening experience with an aggressive dog) may predispose the child to the development of phobic symptoms. Intervention (eg, psychotherapy or medication) in the early stages of symptom development may be beneficial in preventing the worsening of symptoms.
Physicians without expertise in conducting behavioral therapy may want to consult with a psychiatric center specializing in treatment of anxiety disorders, either for guidance on developing a treatment plan or, in more difficult cases, for referral.
Consultation with an internist or a neurologist may be helpful for sorting through the nonpsychiatric differential diagnosis, especially if rare disorders, such as pheochromocytoma, are suspected (see Differentials).
Inpatient treatment is indicated only for patients with a severe phobic disorder who presenting with acute suicidal ideation or attempts. In addition, inpatient treatment (including detoxification, rehabilitation, or both) may be recommended for treatment of secondary drug or alcohol abuse or dependence.
Outpatient follow-up is usually required until the patient’s symptoms have resolved. After the resolution of the symptoms, the physician can attempt to taper pharmacotherapy, as well as monitor for relapse.
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