My bf is on coumadin (warfarin) i'm his gf i have seen in the last month his eyes are turning brownish yellow could it be the coumadin (warfarin)?

Maybe: Coumadin (warfarin) increases the risk of bleeding and bruising. If he has bruising, then the blood break-down product called bilirubin may be high in his blood. This can cause the eyes to appear yellow. He should see his doctor to evaluate this problem.

Disturbing: May be jaundice you are describing this needs evaluation and possible lab testing.