A 55-year-old man presents with impaired hearing and tinnitus in his right ear for three years. No other symptoms are present. There is no history of trauma or prolonged exposure to loud noises. His medical, surgical, and family histories are unremarkable. He is not on any medications, including over-the-counter medicines, or supplements. He only drinks socially, between 2 to 3 standard drinks per week. He does not smoke and does not use recreational drugs. There is no history of allergies. He works as a senior librarian in a nearby public library.