A 60-year-old man presents to the clinic with toenail changes that have been progressively worsening over the past year.

A 60-year-old man presents to the clinic with toenail changes that have been progressively worsening over the past year. The patient’s medical history is notable for type 2 diabetes mellitus, hypertension, and osteoarthritis. Current medications include metformin, lisinopril, and ibuprofen. Vital signs include a temperature of 98.2°F, heart rate of 76 beats per minute, and blood pressure of 120/78 mm Hg. On physical examination, his great toenails show discoloration, subungual hyperkeratosis, and onycholysis. Many other toenails have a yellow discoloration. No other skin or systemic abnormalities are noted. What is the oral antifungal agent with the highest cure rate for treating the most likely condition? Ciclopirox Fluconazole Griseofulvin Pulse-dosed itraconazole Terbinafine