Phobia

Volume 2 Issues 7 July, 2021

Introduction: A specific (isolated) phobia is a condition characterized by marked irrational fear, leading to avoidance of that specific object or situation with associated marked anxiety & emotional distress. Specific phobias are commonly classified as animal type (e.g. insects, dogs), natural-forces type (e.g. storms, water), blood, injection and injury type, and situational type (e.g. elevators, tunnels). Usually, onset is in mid-childhood or early adolescence and if untreated they tend to persist lifelong. Lifetime prevalence of specific phobias is around 12.5% while among children it is as high as 17.6%. Etiology is multifactorial, genetic (heritability: estimated between 30 to 40% as seen in twin studies), conditioning (fear conditioning), non-associative learning, personality factors (anxiety sensitivity), cognitive factors (attentional biases to threat-related information, perceptual and cognitive distortions), social and environmental factors (traumatic event) and evolutionary model (to facilitate survival, preparedness) have been proposed.

Pathophysiology: As for any anxiety disorder limbic system plays a major role in pathophysiology. The amygdala receives sensory information and sends efferent impulses to elicit flight-fight response which includes autonomic arousal (lateral nucleus of hypothalamus), adrenocorticotropic hormone release (paraventricular nucleus of hypothalamus), noradrenaline release (locus ceruleus), increased respiration (parabrachial nucleus), defensive behaviors (periaqueductal gray), startle response (nucleus pontine reticularis), and fearful expressions (facial motor nerve)..

Comorbid conditions: Phobic anxiety often results into panic attacks and significantly affects mobility, socio- occupational functioning, quality of life and help seeking behavior (e.g., poor sugar control in needle and blood injury phobia). Common comorbidities include other phobias like social phobia, depression, substance abuse disorder, separation anxiety disorder, attention deficit and hyperactivity disorder, school refusal, obsessive compulsive disorder, agoraphobia, and anankastic and anxious avoidant personality disorder.

Treatment:

Exposure therapy in the form of graduated exposure to the feared stimulus is most useful when combined with Cognitive Behavioral Therapy. Systematic desensitization and relaxation strategies such as breathing or hyperventilation control, relaxation training are also shown to be effective. An emerging e-therapy as virtual reality treatment are also available in which virtual reality (VR) integrates real-time computer graphics, body tracking devices, visual displays and other sensory input devices to immerse patients in a computer generated virtual environment.

Pharmacotherapy is usually beneficial in treatment in specific phobias. The treatment of phobia yields best results when selective serotonin reuptake inhibitors fluvoxamine, paroxetine, and sertraline or Tricyclic Antidepressant drugs are used along with CBT It can be used either when encounter to phobic stimuli is very occasional; other interventions have been deferred for some reason or when there is failure of non-pharmacological intervention. Commonly used medications before exposure to phobic stimuli are short acting benzodiazepines (such as alprazolam, lorazepam, etc.). Emerging evidence suggests that cycloserine (NMDA receptor partial agonist) may be useful in enhancing the benefits of exposure therapy.