No pain, no itching, just red eyes. condition i've had throughout my life. tried many eye drops, mostly artificial tears. ways to prevent redness?

Scleritis?: You may have allergies and there are some good allergy drops that can help. Play detective and avoiding irritants can also help (second hand smoke for example, etc). Visine may be an option too, simply to "get the red out", but having yourself officially diagnosed as to why your eyes are always red, is your best option, and an ophthalmologist would be the dr., to see. Best wishes.

Many possibilities: It can be way too many things to list, such as chronic allergies, pterygium, chronic dry eyes, large blood vessels, etc. An ophthalmologist would be able to tell. The one thing you don't want to start doing is self treating with very dangerous eye drops, such as visine and clear eyes, which will certainly make it worse. Start with an ophthalmology exam and go from there. Feel better.

Many possible causes: There are many causes of redness of the eyes. Several types of inflammatory conditions, allergic reactions, detergents, chemicals, and sometimes bacterial, viral or fungal infections can cause redness of the eyes. Have it evaluated by a professional and get the appropriate treatment.