Blood phobia

Blood phobia (also, AE: Hemophobia, BE: Haemophobia) is the extreme and irrational fear of blood. Like trypanophobia and traumatophobia, acute cases of this fear can cause physical reactions that are uncommon in most other fears, specifically Vasovagal Syncope (fainting). These three phobias are often categorized as "blood-injection-injury phobia" (the phrasing used by the DSM-IV) or "blood-injury-illness phobia."

Etiology
Blood phobia is often caused by direct or vicarious trauma in childhood or adolescence. There is also a genetic component to blood phobia.

Treatment
In patients with vasovagal blood phobia, patients who are successfully treated with psychological interventions are seen as unique. In contrast, many behavioral techniques useful in mitigating vasovagal syncope, such as applying tension to the muscles in an effort to increase blood pressure, are helpful to patients with blood phobia. Medical devices, such as pacemakers, are also used to treat patients with blood-phobia.