Long-term smokers, especially those who smoke in the morning on an empty stomach, may develop “smoke-toxicity” and experience reduced vision in both eyes with red color blindness and a normal fundus or optic nerve atrophy. Visual field examination shows an oval or dumbbell-shaped dark spot between the central gaze point and the blind spot. For this disease, treatment starts with smoking cessation, intramuscular injection of long-acting vitamin B12 (250mg 1/day, 10 times); intravenous sodium thiosulfate (30-40ml, 1/day, 10 times); oral cystine 4g daily for 4-6 months; vitamin B6 30mg/day.