Blood phobia

Blood phobia, also called hemophobia or hematophobia, is an intense and persistent fear of blood classified among the blood-injection-injury phobias. Unlike most specific phobias, which raise heart rate under threat, severe blood phobia frequently triggers a vasovagal response that drops heart rate and blood pressure, causing lightheadedness or fainting. Physical symptoms during an episode can include a racing heart followed by a sudden crash, breathing difficulty, trembling, chest tightness, sweating and nausea, alongside intense anxiety and a strong urge to escape any blood-related situation. The blood-injection-injury phobia group as a whole is estimated to affect around four percent of the population in the United States, and its distinctive fainting response is attributed to vagus nerve activity rather than ordinary fear circuitry.