Regarding retinal diseases like macular degeneration and diabetic retinopathy the preclinical studies are excellent in that they show specific prevention and deal directly with multiple pathways of protection to the retina. A major factor in all retinal disease is inflammation and oxidative stress. Like the brain, the eye also has a barrier to many substances and that includes many medicines. But, that is not true for CBD. It passes into the eye circulation, stops inflammation, prevents abnormal blood vessel formation and prevents the retinal and support cells from dying. I recommend at least 60mg per day. And, in people without MD, an adequate dose of CBD enhances vision immediately improving visual definition in distance vision and color appreciation. Patient should avoid buying new lenses or glasses because they might just have to use their previous eye prescription, at least that is what they tell me.