There are four types of hypersensitivity reaction, classified according to the way in which the ALLERGEN or ANTIGEN activates the reaction. The classic allergic reaction is the type I hypersensitivity reaction, with exposure to an external substance (the allergen) initiating the IMMUNE RESPONSE.
Flickering lights in vision, Headache and Sudden flash of lights. WebMD Symptom Checker helps you find the most common medical conditions indicated by the symptoms flickering lights in vision, headache and sudden flash of lights including Migraine headache (adult), Tension headache, and Ocular migraine.
Are flashing lights in the field of vision always indicative of eye problems? No, flashing lights are not always ocular in origin. People experiencing a TIA (a transient ischemic attack, which may be an early warning sign of impending stroke) sometimes report flashing lights.