@sueinmn . Thank you, Sue, for sharing your doctor's policy regarding cataract surgery and ethambutol. It seems like reasonable precautions to take. I will discuss again with my doctor. Meanwhile, I got a a reply from her about the question of my ethambutol dosage. It's actually on the low end. I was forgetting that the mg. on the bottle represent the mg. per kg. of body weight. x my weight in kg. So at least that worry is relieved!