Oral medications include terbinafine (76% effective), itraconazole (60% effective) and fluconazole (48% effective). They share characteristics that enhance their effectiveness: prompt penetration of the nail and nail bed, and persistence in the nail for months after discontinuation of therapy. Ketoconazole by mouth is not recommended due to side effects. Oral terbinafine is better tolerated than itraconazole. For superficial white onychomycosis, systemic rather than topical antifungal therapy is advised.
Infected nails are usually thicker than normal and could be warped or oddly shaped. They can break easily. Nails with fungus might look yellow. Sometimes a white dot shows up on the nail and then gets bigger. When fungus builds up under your nail, it can loosen and even separate the nail from the bed. The fungus can also spread to the skin around your nail.