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Specific Phobias

Specific Phobias

Specific phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder is irrational fear or anxiety Anxiety Feelings or emotions of dread, apprehension, and impending disaster but not disabling as with anxiety disorders. Generalized Anxiety Disorder arising from a specific object or situation, leading to avoidance. The main types of phobias Phobias Neurological Examination are animal (e.g., spiders, dogs), natural environment (e.g., water, storms), blood-injection injury (e.g., needles), situational (e.g., enclosed spaces), and others not categorized under the preceding specifiers. The symptoms cause functional impairment and persist for ≥ 6 months. CBT is 1st-line treatment; medications have a limited role.

Last updated: 6 Jul, 2021

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Contents

Overview

Definition

A phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder is defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. 

Epidemiology

  • The estimated lifetime prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency of social phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder in the United States is 7%–12.5%.
  • More common in females than in males
  • Bimodal age at onset:

Pathophysiology

  • Genetics Genetics Genetics is the study of genes and their functions and behaviors. Basic Terms of Genetics: 
    • 1st-degree relatives of individuals with specific phobias Phobias Neurological Examination have an increased risk (up to 31%) of having the disorder, but with a different stimulus. 
    • Twin studies point to a stronger influence of environmental factors than genetic factors.
  • Neurobiologic: Hyperactivation of the amygdala Amygdala Almond-shaped group of basal nuclei anterior to the inferior horn of the lateral ventricle of the temporal lobe. The amygdala is part of the limbic system. Limbic System: Anatomy and insula (structures involved in negative emotional responses) has been associated with phobic disorders.
  • Personality traits:
    • Disgust sensitivity Sensitivity Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Blotting Techniques: predisposition to experience disgust in response to certain stimuli (certain animals Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, animalia was one of the kingdoms. Under the modern three domain model, animalia represents one of the many groups in the domain eukaryota. Cell Types: Eukaryotic versus Prokaryotic or blood injections)
    • Anxiety sensitivity Anxiety sensitivity Fear of the sensations or behaviors of anxiety due to the belief that the anxiety symptoms are harmful. Agoraphobia: fear of the sensations or behaviors of anxiety due to the belief that the anxiety symptoms are harmful
  • Environmental factors:
    • Traumatic events, the associated stress, prior and subsequent exposure Exposure ABCDE Assessment to a stimulus, and the support obtained affect Affect The feeling-tone accompaniment of an idea or mental representation. It is the most direct psychic derivative of instinct and the psychic representative of the various bodily changes by means of which instincts manifest themselves. Psychiatric Assessment specific phobias Phobias Neurological Examination.
    • Processes that lead to fear development:
      • Direct conditioning: being hurt or frightened or having the feeling of helplessness leads to anxiety toward the situation/subject.
      • Vicarious acquisition: observing someone with the fearful or anxious behavior
      • Informational transmission: obtaining information from others or through media (e.g., shark attacks, plane crashes)

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11:50
Phobias

Clinical Presentation and Diagnosis

Specifiers

Main types of specific phobias Phobias Neurological Examination based on the nature of the stimulus:

  • Animal:
    • Spiders: arachnophobia
    • Dogs: cynophobia
    • Insects: entomophobia
  • Natural environment:
    • Heights: acrophobia
    • Water: aquaphobia 
    • Thunderstorms: astraphobia
  • Blood-injection injury:
    • Injections/needles: trypanophobia or belenophobia
    • Dental procedure: odontophobia 
  • Situational:
  • Other (cannot be categorized as above):
    • Costumed characters: masklophobia
    • Loud sounds: phonophobia or ligyrophobia
    • Vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia: emetophobia

Clinical features and diagnosis

  • Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with:
    • Excessive anxiety about, or fear of, a specific object or situation
    • This behavior is almost always provoked when exposed to the stimulus:
      • Intense fear, with physiologic arousal (↑ HR or BP)
      • Crying, clinging, freezing in children
    • Avoidance behavior
    • The fear and anxiety lead to functional impairment (e.g., avoids travel because of fear of flying, cannot find a job because of fear of driving).
  • Symptoms persist ≥ 6 months
  • The fear and anxiety is not due to any underlying medical condition mental disorder or to substance abuse.
  • Diagnosis is based on the presenting symptoms.
  • Without treatment, the phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder persists throughout the lifetime.

Management

  • Specific phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder is treatable, but very few patients seek treatment. 
  • Psychotherapy Psychotherapy Psychotherapy is interpersonal treatment based on the understanding of psychological principles and mechanisms of mental disease. The treatment approach is often individualized, depending on the psychiatric condition(s) or circumstance. Psychotherapy:
  • Pharmacotherapy: 
    • Generally, medications alone are not useful in this disorder except in certain situations, as anxiety may return upon discontinuation of medications. 
    • Short-acting benzodiazepines Benzodiazepines Benzodiazepines work on the gamma-aminobutyric acid type A (GABAA) receptor to produce inhibitory effects on the CNS. Benzodiazepines do not mimic GABA, the main inhibitory neurotransmitter in humans, but instead potentiate GABA activity. Benzodiazepines might be used in patients with claustrophobia Claustrophobia Magnetic Resonance Imaging (MRI) (fear of enclosed places, such as an MRI machine). 
    • D- cycloserine Cycloserine Antibiotic substance produced by streptomyces garyphalus. Antimycobacterial Drugs (DCS): 
      • Partial N-methyl-d- aspartate Aspartate One of the non-essential amino acids commonly occurring in the l-form. It is found in animals and plants, especially in sugar cane and sugar beets. It may be a neurotransmitter. Synthesis of Nonessential Amino Acids (NMDA) receptor Receptor Receptors are proteins located either on the surface of or within a cell that can bind to signaling molecules known as ligands (e.g., hormones) and cause some type of response within the cell. Receptors agonist 
      • Investigational, but shows some evidence of augmenting CBT during exposure Exposure ABCDE Assessment therapy

Other Anxiety Disorders

The following table summarizes the most important information about anxiety disorders.

Table: Comparison of anxiety disorders
Condition Most important features Duration Treatment
Panic disorder Panic disorder Panic disorder is a condition marked by recurrent and episodic panic attacks that occur abruptly and without a trigger. These episodes are time-limited and present with cardiorespiratory (palpitations, shortness of breath, choking), GI (nausea, abdominal distress), and neurologic (paresthesias, lightheadedness) symptoms. Panic Disorder Recurrent and unexpected abrupt surges (within minutes) of intense fear or discomfort ≥ 1 month
Generalized anxiety disorder Generalized anxiety disorder Generalized anxiety disorder (GAD) is a common mental condition defined by excessive, uncontrollable worrying causing distress and occurring frequently for at least 6 months. Generalized anxiety disorder is more common in women. Clinical presentation includes fatigue, low concentration, restlessness, irritability, and sleep disturbance. Generalized Anxiety Disorder Chronic multiple worries usually about issues, events, activities ≥ 6 months Combination of antidepressants ( SSRIs SSRIs Serotonin Reuptake Inhibitors and Similar Antidepressants) and CBT
Specific phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder Unreasonable fear of a certain object or situations ≥ 6 months
  • 1st-line: CBT
  • Medication has an insignificant role.
Social phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder ( social anxiety disorder Social anxiety disorder Social anxiety disorder, or social phobia, is a psychiatric illness marked by fear and avoidance of social interactions due to concerns about embarrassment. The disorder usually occurs in more than one social situation for more than 6 months and leads to a significant decline in function. Social Anxiety Disorder) Fear or avoidance of social interactions due to concerns about being embarrassed ≥ 6 months
Agoraphobia Agoraphobia Agoraphobia is fear or anxiety in a situation that would be difficult to leave or to obtain help in the event that one develops panic-like symptoms. Situations include being in public or open spaces, lines, crowds, or public transport. Agoraphobia Fear of being in situations or places where it is difficult to leave or escape Escape With constant immune mechanisms holding unstable tumor cells in equilibrium, tumor-cell variants may emerge. These cancer cells may express fewer antigens on their surfaces or lose their MHC class I expression.Variants may also protect themselves from T-cell attack via expression of IC molecules on their surfaces, like normal cells.Creation of an immunosuppressive state in the microenvironment is another way to grow without immunologic interference. Cancer Immunotherapy ≥ 6 months 1st-line: SSRIs SSRIs Serotonin Reuptake Inhibitors and Similar Antidepressants or CBT
Separation anxiety disorder Fear of being separated from attachment Attachment The binding of virus particles to virus receptors on the host cell surface, facilitating virus entry into the cell. Virology figures ≥ 1 month
  • 1st-line: CBT
  • Medications might be used if CBT alone fails.
Illness anxiety disorder Illness Anxiety Disorder Illness anxiety disorder, formerly known as hypochondriasis, is a chronic condition characterized by a prolonged and exaggerated concern about one’s health and possible illness. Patients fear or are convinced that they have a disease and interpret minor or normal bodily symptoms as signs of a serious medical condition. Illness Anxiety Disorder Anxiety Anxiety Feelings or emotions of dread, apprehension, and impending disaster but not disabling as with anxiety disorders. Generalized Anxiety Disorder arises from concerns about having or acquiring a certain illness. ≥ 6 months
  • Schedule regular Regular Insulin follow-up visits.
  • Avoid doing unnecessary diagnostic tests Diagnostic tests Diagnostic tests are important aspects in making a diagnosis. Some of the most important epidemiological values of diagnostic tests include sensitivity and specificity, false positives and false negatives, positive and negative predictive values, likelihood ratios, and pre-test and post-test probabilities. Epidemiological Values of Diagnostic Tests.
  • Avoid referrals.
  • CBT and antidepressants if these measures fail
Substance- or drug-induced anxiety disorder
  • Intoxication with cocaine Cocaine An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake. Local Anesthetics or amphetamine
  • Withdrawal from alcohol or benzodiazepines Benzodiazepines Benzodiazepines work on the gamma-aminobutyric acid type A (GABAA) receptor to produce inhibitory effects on the CNS. Benzodiazepines do not mimic GABA, the main inhibitory neurotransmitter in humans, but instead potentiate GABA activity. Benzodiazepines
  • Medications such as β2-agonists ( albuterol Albuterol A short-acting beta-2 adrenergic agonist that is primarily used as a bronchodilator agent to treat asthma. Sympathomimetic Drugs) or levothyroxine Levothyroxine Thyroid Replacement Therapy
BDZs: benzodiazepines Benzodiazepines Benzodiazepines work on the gamma-aminobutyric acid type A (GABAA) receptor to produce inhibitory effects on the CNS. Benzodiazepines do not mimic GABA, the main inhibitory neurotransmitter in humans, but instead potentiate GABA activity. Benzodiazepines
SSRIs SSRIs Serotonin Reuptake Inhibitors and Similar Antidepressants: selective serotonin Serotonin A biochemical messenger and regulator, synthesized from the essential amino acid l-tryptophan. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Receptors and Neurotransmitters of the CNS reuptake inhibitors

Differential Diagnosis

  • Panic disorder Panic disorder Panic disorder is a condition marked by recurrent and episodic panic attacks that occur abruptly and without a trigger. These episodes are time-limited and present with cardiorespiratory (palpitations, shortness of breath, choking), GI (nausea, abdominal distress), and neurologic (paresthesias, lightheadedness) symptoms. Panic Disorder: chronic mental disorder marked by recurrent and episodic panic attacks that occur abruptly without a trigger Trigger The type of signal that initiates the inspiratory phase by the ventilator Invasive Mechanical Ventilation. Panic disorder Panic disorder Panic disorder is a condition marked by recurrent and episodic panic attacks that occur abruptly and without a trigger. These episodes are time-limited and present with cardiorespiratory (palpitations, shortness of breath, choking), GI (nausea, abdominal distress), and neurologic (paresthesias, lightheadedness) symptoms. Panic Disorder is associated with anxiety or fear of having another attack or its complications and some behavioral changes. If the panic attack Panic attack A panic attack is not a mental disorder. Rather, this disorder is a sudden, spontaneous, time-limited period (minutes to an hour) of heightened anxiety or intense fear, often with physical symptoms. Panic Disorder is triggered by a known, identified trigger Trigger The type of signal that initiates the inspiratory phase by the ventilator Invasive Mechanical Ventilation, then the correct diagnosis would be specific phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder. 
  • Social phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder: also called social anxiety disorder Social anxiety disorder Social anxiety disorder, or social phobia, is a psychiatric illness marked by fear and avoidance of social interactions due to concerns about embarrassment. The disorder usually occurs in more than one social situation for more than 6 months and leads to a significant decline in function. Social Anxiety Disorder (SAD). Social phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder is the fear or avoidance of social interactions because of concerns about being embarrassed, occurring in > 1 social situation for > 6 months. Treatment includes CBT, antidepressants ( SSRIs SSRIs Serotonin Reuptake Inhibitors and Similar Antidepressants, serotonin Serotonin A biochemical messenger and regulator, synthesized from the essential amino acid l-tryptophan. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Receptors and Neurotransmitters of the CNS– norepinephrine Norepinephrine Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers, and of the diffuse projection system in the brain that arises from the locus ceruleus. Receptors and Neurotransmitters of the CNS reuptake inhibitor ( SNRIs SNRIs Serotonin Reuptake Inhibitors and Similar Antidepressants)), and β-blockers for performance-only subtypes. People with social phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder are afraid of being negatively judged by others.  
  • Intoxication (on cocaine Cocaine An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake. Local Anesthetics or hallucinogens): Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with cocaine Cocaine An alkaloid ester extracted from the leaves of plants including coca. It is a local anesthetic and vasoconstrictor and is clinically used for that purpose, particularly in the eye, ear, nose, and throat. It also has powerful central nervous system effects similar to the amphetamines and is a drug of abuse. Cocaine, like amphetamines, acts by multiple mechanisms on brain catecholaminergic neurons; the mechanism of its reinforcing effects is thought to involve inhibition of dopamine uptake. Local Anesthetics use disorder or hallucinogen use disorder Hallucinogen use disorder Hallucinogen use disorder is defined by the pathologic consumption of hallucinogenic substances that cause perceptual distortions (visual or auditory). Examples include psilocybin (mushrooms), lysergic acid diethylamide (LSD), and phencyclidine (PCP). These drugs are used for their psychedelic effects. Hallucinogen Use Disorder can develop a specific phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder when they are intoxicated with either substance. Symptoms of intoxication include agitation Agitation A feeling of restlessness associated with increased motor activity. This may occur as a manifestation of nervous system drug toxicity or other conditions. St. Louis Encephalitis Virus, psychosis, hemodynamic instability ( hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension, tachycardia Tachycardia Abnormally rapid heartbeat, usually with a heart rate above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia. Sepsis in Children), diaphoresis, and mydriasis Mydriasis Dilation of pupils to greater than 6 mm combined with failure of the pupils to constrict when stimulated with light. This condition may occur due to injury of the pupillary fibers in the oculomotor nerve, in acute angle-closure glaucoma, and in adie syndrome. Glaucoma. Acute intoxication is distinguished from specific phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder by history taking, physical exam, and urine Urine Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the urethra. Bowen Disease and Erythroplasia of Queyrat toxicology screen. 
  • Agoraphobia Agoraphobia Agoraphobia is fear or anxiety in a situation that would be difficult to leave or to obtain help in the event that one develops panic-like symptoms. Situations include being in public or open spaces, lines, crowds, or public transport. Agoraphobia: fear or anxiety occurring while facing different situations in which it would be difficult to leave or to obtain help in the event of having panic-like symptoms. Situations include being in public or open spaces, crowds, or public transport. In specific phobia Phobia A phobia can be defined as an irrational fear that results in avoidance of the feared subject, activity, or situation. Social Anxiety Disorder, multiple fears are present (e.g., getting hurt by a spider Spider Arthropods of the class arachnida, order araneae. Except for mites and ticks, spiders constitute the largest order of arachnids, with approximately 37, 000 species having been described. The majority of spiders are harmless, although some species can be regarded as moderately harmful since their bites can lead to quite severe local symptoms. Spider Bites, being stuck in an elevator). In agoraphobia, there is fear of panic symptoms and being unable to get help or escape Escape With constant immune mechanisms holding unstable tumor cells in equilibrium, tumor-cell variants may emerge. These cancer cells may express fewer antigens on their surfaces or lose their MHC class I expression.Variants may also protect themselves from T-cell attack via expression of IC molecules on their surfaces, like normal cells.Creation of an immunosuppressive state in the microenvironment is another way to grow without immunologic interference. Cancer Immunotherapy.

References

  1. Choy, Y. (2018). Treatment of specific phobias of clinical procedures in adults. UpToDate. Retrieved June 26, 2021, from https://www.uptodate.com/contents/treatment-of-specific-phobias-of-clinical-procedures-in-adults
  2. Dave, P. (2017). Clinical management of anxiety disorders. Retrieved June 22, 2021. https://www.researchgate.net/publication/348489972_Clinical_Management_of_Anxiety_Disorders
  3. Grant, J. (2021). Overview of anxiety disorders. Retrieved June 22, 2021. https://www.researchgate.net/publication/348495093_Overview_of_Anxiety_Disorders
  4. McCabe, R. (2021). Specific phobia in adults: Epidemiology, clinical manifestations, course and diagnosis. UpToDate. Retrieved June 26, 2021, from https://www.uptodate.com/contents/specific-phobia-in-adults-epidemiology-clinical-manifestations-course-and-diagnosis 
  5. Palkar, P. (2020). Neurobiology of anxiety disorders. Retrieved June 22, 2021, from https://www.researchgate.net/publication/341407589_Neurobiology_of_Anxiety_Disorders
  6. Sadock, B. J., Sadock, V. A., Ruiz, P. (2014). Anxiety disorders. Chapter 9 of Kaplan and Sadock’s Synopsis of Psychiatry: Behavioral Sciences/Clinical Psychiatry, 11th ed. Philadelphia: Lippincott Williams and Wilkins, pp. 387–417.

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