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.
Other eye or visual symptoms that may occur along with peripheral vision loss. Peripheral vision loss may accompany other symptoms affecting the eye or your vision including: 1  Abnormal pupil size or nonreactivity to light. 2  Glare or halos around lights. 3  Increased sensitivity to light. 4  Poor nighttime vision. 5  Red, sore eyes (bloodshot eyes). 6  Seeing floating objects or flashing lights in your vision.