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Phobic disorders are a group of different phobias that are collectively more common compared to any other psychiatric disorder. Phobic disorders include social phobia, specific phobia, and agoraphobia. The phobia can be mild or severe. The severity of the condition can be determined from the impact on the individual’s ability to work, travel and socially interact with others.

A phobia can be defined as the irrational fear that results in avoidance of the feared subject, activity or situation. Patients with phobic disorders might have a good insight and know that their fear is excessive or might have poor insight.

Epidemiology of Phobic Disorders

Phobic disorders collectively are far more common than any other psychiatric disorder, including mood disorders, anxiety disorders, and substance abuse. The estimated prevalence of social phobia in the United States is 7%, whereas the prevalence of agoraphobia is around 1.7%. Specific phobias collectively have a similar prevalence to social phobia, i.e. 7 to 9%.

Social phobia is more common in the United States compared to other regions around the world. For instance, the estimated prevalence of social phobia in Europe is around 2%. Specific phobias are less common in Asian, African and Latin American countries compared to the United States.

Social phobia, also known as social anxiety disorder, usually starts during late childhood and early adolescent years. The emergence of new-onset social phobia in an adult warrants a full medical examination and sophisticated investigations to exclude an organic cause.

Specific phobias also appear during childhood. The prevalence of specific phobias in adults is estimated to be around one-third of that in children. This might be explained by a decrease in the severity of the symptoms during adulthood. On the other hand, agoraphobia is more common in adults compared to children. All types of phobic disorders are found more common in females compared to males.

The prognosis of phobic disorders is dependent on the severity of the condition, how motivated is the patient to receive treatment, the level of support and the ability to comply with a management plan. Additionally, the prognosis is dependent on the type of phobia that is in question. For instance, specific phobias usually respond very well to treatment, while social phobia usually does not.

Pathophysiology of Phobic Disorders

To understand the pathology in phobic disorders, one should focus on two important aspects: the biologic basis of the condition, and the psychological pathology. It is now acceptable that patients with phobic disorders have some form of dysregulation in the endogenous biogenic amines. The sympathetic nervous system is over-activated in these patients which is responsible for the different symptoms of phobic disorders.

Psychological theories try to explain the pathology of phobic disorders from another perspective. One theory states that the anxiety that is experienced in the different phobic disorders is, in fact, a displacement defensive mechanism of intrapsychic conflict. Others think that social anxiety might be more related to low self-esteem or other unresolved conflicts. Others see phobias as a learned behavior where one associates certain responses to certain stimuli.

Brain imaging studies have also helped us understand which neural circuits might be impaired or dysregulated in patients with phobic disorders. In general, patients with phobic disorders show increased activation of the prefrontal, orbitofrontal, and anterior cingulate cortex. The amygdala is also over-activated in patients with phobic disorders. These brain regions are known to be related to executive functioning, behavior, and emotion processing.

Diagnostic Criteria for Phobic Disorders

Phobic disorders are now classified into three main diagnoses:

Social anxiety disorder is the strong and persistent fear of an interpersonal situation where one must interact with others. The fear is usually related to the anticipation of embarrassment.

Specific phobias are strong and persistent fears of a certain object or situation. The fear response is induced only when the object or situation is present.

Agoraphobia is defined as the fear of being alone in a public place because the patient is afraid if he or she experiences a panic attack, they will not be able to find an exit quickly.

Social anxiety disorder or social phobia

For the diagnosis of social phobia to be made, the patient should show excessive fear and anxiety that is induced by certain social interactions, such as meeting unfamiliar people, being observed while eating or drinking, performing in front of others or giving a talk or a speech. The fear should stem from the belief that the individual will be judged and evaluated.

The symptoms should be provoked almost always by the same stimuli. The patient should show avoidance behavior of social interaction because of this fear. The fear should be out of proportion to the rational threat that might be posed by the social situation.

The symptoms should last for six months or longer. The impairment in life should affect different aspects, such as occupational, social and academic performance. Finally, other disorders such as body dysmorphic disorder, autism disorder, or other medical conditions that might cause the symptoms should be excluded.

Specific Phobia

The diagnostic criteria for specific phobias are the same as for social phobia but the main difference is in the stimulus that induces the fear. The stimuli in specific phobia can be flying, heights, certain animals, receiving an injection or seeing blood. Fear of animals can be specified in the diagnosis. A fear of heights is known as acrophobia, whereas fear of blood and injections can be diagnosed as a fear of needles or invasive medical procedures. Most patients with specific phobias have multiple fears.


Patients with agoraphobia show a marked fear and anxiety of at least two of the following:

  1. Using public transportation
  2. Being in open spaces
  3. Being in enclosed spaces
  4. Standing in line or being in a crowd
  5. Being outside the home alone

Avoidance behavior is also needed for the diagnosis and the patient should show evidence that he or she is avoiding being in the specific situations mentioned above. Because of the intense fear, the patient is expected to go out only with a companion.

The other diagnostic criteria for agoraphobia, such as the duration of the symptoms, the persistent provoking of the symptoms by the same stimuli, the presence of occupational or social impairment and the exclusion of other medical or mental disorders that might cause similar symptoms, are the same as for the other phobic disorders.

Treatment of Phobic Disorders

Pharmacologic treatment of social phobia

Paroxetine, sertraline, escitalopram, fluoxetine, venlafaxine, and phenelzine have all shown good efficacy in decreasing the severity of the social phobia.

Pharmacologic treatment of specific phobia

Pharmacotherapy is not effective in managing the symptoms of specific phobias. Benzodiazepines might be used to lower the anxiety symptoms before being exposed to the provoking stimulus, i.e. before going onto an airplane.

Pharmacologic treatment of agoraphobia

The symptoms of agoraphobia also respond to escitalopram, fluoxetine, fluvoxamine, paroxetine, and sertraline. Benzodiazepines can be also used to lower the anxiety symptoms experienced by patients with agoraphobia.

Psychotherapy in phobic disorders

The most effective approach to treat social or agoraphobia is the combination of behavioral therapy or cognitive behavioral therapy and pharmacotherapy. Panic disorders and specific phobias can be managed by computerized cognitive behavioral therapy aiming to desensitize the patient to the stimulus.

Exposure therapy is also usually effective in specific phobias. Cognitive-behavioral therapy in specific phobias is very effective and has been found to alter the abnormal brain regions involved with the condition on follow-up functional magnetic resonance imaging studies.

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