Headache and nausea after a watery flash in front of the eyes may be vitreous clouding or triggered by migraine. Vitreous clouding mainly refers to the appearance of opaque objects in the vitreous body, which will lead to blurred vision, feel like flying mosquitoes in front of the eyes, black shadows, clouds, etc., more is the vitreous body with the age of liquefaction, detachment, or vitreous inflammation, hemorrhage and other diseases caused. When the disease is more serious, it may also be accompanied by headache, nausea and other phenomena. Migraines with aura may also be present. Migraines with aura may cause the eyes to show watery or flashing highlights, and may be accompanied by an enlarged blind spot in the visual field. Some patients may experience severe pain and nausea on the same side of the head. Patients with headache and nausea after the watery flash in front of the eyes are advised to go to the hospital for timely examination and follow the doctor’s instructions.