Gray nails are a common fungal disease caused by a fungal infection of the nail plate and the underlying nail tissue. Topical antifungal medications are applied topically to treat the condition. If the patient’s condition is not well controlled, oral antifungal medications may be combined with the treatment. The topical antifungal medications include ciclopirox, amorolfine, tincture of iodine, and tioconazole solution, while the oral antifungal medications include itraconazole, terbinafine, and fluconazole. Patients should try to remove the diseased nails before applying the drugs externally, because the drugs cannot play an effective role through the thick diseased nails. Amorolfine is commonly used clinically and is recommended to be applied 1-2 times a week for about 48 weeks, or longer if the condition is severe.