Hemalgia, a syncope phenomenon that occurs in some people due to the sight of blood, mainly manifests as dizziness, nausea, dizziness, palpitations, followed by pallor, cold sweat, cold extremities, reduced blood pressure, weak pulse and even sudden loss of consciousness. If it is an acute attack, first of all, the patient should lie down, feed warm water or sugar water, rest for 10-15 minutes, and can generally recover. If it is serious and blood pressure continues to decrease, infusion can be given to apply antihypertensive drugs. To eradicate hematemesis, it is necessary to ask a psychiatrist for desensitization treatment. Under the guidance of a psychiatrist, repeated and gradual comforting persuasion from weak to strong, repeated treatment can eventually cure the disease.