The 53-year-old former NFL wide receiver posted an Instagram photo of himself Tuesday at UCLA Ronald Reagan Hospital in Los Angeles.
Irvin revealed for the last two months, he has been dealing with persistent throat issues.
He says he is terrified he might have throat cancer, which claimed his father's life at the age of 51.
Irvin underwent treatment on Sunday and Monday. A biopsy was performed by doctors in hopes of diagnosing the problem.