Why are the whites of the eyes yellow and bloodshot?

Apr 12, 2022 Source: Cainiu Health
Disease description:

Yesterday, my husband mentioned that the whites of my eyes appeared slightly yellowish and had visible blood vessels. What causes yellowing of the sclera accompanied by bloodshot eyes?

Doctor's answer (1)
Dr. Chen You
Yellowing of the sclera (the “white part” of the eye) with accompanying blood vessels may indicate a pinguecula—typically located adjacent to the cornea (the “black part” of the eye)—caused primarily by degenerative changes and hyperplasia of the conjunctival tissue. However, it may also represent simple pigment deposition, commonly associated with aging, chronic sun exposure, or irritation from foreign bodies, leading to melanin accumulation in the bulbar conjunctiva. Additionally, this presentation cannot exclude other potential causes such as conjunctivitis or ocular fatigue.