22nd February 2024

Phobia Disorder

Background

Phobia disorder is the most prevalent and most treatable of the psychiatric disorders, with women believed to be three times more likely to be affected. It occurs when there is an excessive fear involving a particular situation/object (phobic stimuli), which is disproportionate to the danger or threat it poses. This results in anxiety, distress, discomfort, and avoidance of the phobic stimuli, all of which can impact an individual’s day to day functioning. Individuals with phobias experience hyperactivation of their amygdala when they are exposed to phobic stimuli. Phobia disorders can also present with physical symptoms due to overactivity of the parasympathetic nervous system, following exposure to the phobic stimuli. For example, the vasovagal syncope that occurs in needle phobic individuals whilst having their bloods. 

Examples of phobic stimuli include:

• Animals – mice, spiders, or dogs 
• Nature – heights, water, darkness, thunderstorms, or fire 
• Medical – procedures, blood taking, injections, or COVID-19 
• Situational – tight spaces, flying on a plane, or lifts 
• Non-specific, e.g clowns, loud noises, etc

Presentation

• Anxiety, fear or dread of a certain object or situation 
• Being repulsed
• Avoidance of phobic stimuli 
• Tachycardia, fainting, sweating, hyperventilation, and other signs of sympathetic nervous system activity. 
• Nausea
• Dizziness
• Becoming overly jumpy

Investigations

The Anxiety Disorders Interview Schedule for DSM-5 (AIDS-5): A structured interview which can be used to diagnose phobia disorders, mood, and a variety of other anxiety disorders. 

This diagnostic interview schedule is usually used in academic settings, however, can also be used in a clinical setting to diagnose phobic disorder. 

Diagnosis 

Diagnosis is usually based on the history. Patients will describe symptoms caused by sympathetic nervous system stimulation when they face the phobic stimuli.  

Organic causes of the physical symptoms should be considered first if a phobic stimulus isn’t obvious on first presentation.

Treatment 

• CBT is the first line treatment, consisting of 1-5 sessions. It involves challenging the negative emotions associated with exposure to the phobic stimuli. 
• Exposure therapy. Used in addition to CBT in those with avoidant behaviours. When an actual threat isn’t present, the body will remain anxious for a short period of time until habituation occurs. This is when anxiety levels or fear begin to decrease. Exposure therapy causes the individual to be exposed to what they fear, without being able to avoid, distract themselves or seek any soothing behaviours, until habituation occurs. With each exposure event, the levels of anxiety are expected to decrease.
  • Direct exposure – phobic stimuli, pictures, video clips or VR are used to produce disgust or fear
  • Interoceptive stimuli – physical sensations feared by individuals are recreated, for example in those fearful of becoming short of breath in certain situations are encouraged to hold their nose to recreate a sense of shortness of breath.  
• Applied tension therapy. Used in those with blood-injection-injury phobias. Individuals are encouraged to repeatedly tense and relax the muscles in their abdomen and limbs. This is thought to increase their blood pressure and heart rate and prevent a vasovagal episode when, for example, having their blood taken. 
• Pharmacotherapy. Benzodiazepines are used in the short term to calm individuals, for example for medical tests e.g. MRI or procedures e.g. endoscopy. SSRIs are used in those with co-morbid mood or anxiety disorders. 

References

• Huberman A. Phobias [Internet]. Phobias – Symptoms, diagnosis and treatment | BMJ Best Practice. 2022 [cited 2023Apr29]. Available from: https://bestpractice.bmj.com/topics/en-gb/693 
• Brown TA, Barlow DH. Anxiety and related disorders interview schedule for DSM-5 (adis-5), Lifetime version: Client interview schedule. Oxford: Oxford University Press; 2014. 
• Streeruwitz A, Hagger M, Webb S, Walker D, Jakeman N. Anxiety, obsession, and reactions to stress. In: Psychiatry PRN. Oxford, New York: Oxford University Press; 2009. p. 154–5.