My husband always have a relatively red eyes. but he said that he feels nirmal about it. what could be the reason for this?

One of many: Red eye can be due to one of the following 1pink eye is a inflammation can be caused by allergy, infection by viruses, bacteria, viruses and toxins 2uveitis it is an inflammation of the eyes , it can be a sign of systemic disease like rhematoid arthritis and other collagen diseases 3dry eye is due to lack of tears 4frequent use of over the counter eye drops 5contact lens wear 6glaucoma check md.