How can I clear up an infection on my thumbnail?

Certainly there are other antifungal medications in addition to Exelderm, but if this product has been used on the nail for four years and the infection is still present, I strongly recommend seeing a dermatologist since no definite diagnosis has been made. Any condition that lasts for this length of time could be potentially serious. As for cutting the nail to the level of the infection, I wouldn’t recommend this because a dermatologist first needs to determine whether it is actually a fungal infection. --The Nail Doctor