Reply To: Hi, Every time when I take 5000 IU vitamin D I get very red irritated eyes after 2-3 days. I have tried taking lot's of different brand vitamin D supps, dry and oil based but every time after 2-3 days my eyes gets really irritated. I get really good physical feeling from vitamin D, the only problem is my eyes. What should I do, I can't live with these irritated eyes, they are unbearable, but I have such a good feeling otherwise with vitamin D, much better than without it. Please help.