I had what you decribed happen to one of my tiger salamanders. I treated it with a terbinafine hydrochloride (generic name for Lamisil) solution. I mixed 1 ml of terbinafine hydrochloride cream to 200 ml of distilled water. Set the solution up 24 hours prior to using it. Soak the frog in the solution for 10 minutes daily for 10 days. A deli cup with a lid makes the perfect container to soak the frog in. Within a few days of its first treatment, you should begin to see improvement. You should continue with all ten treatments, even if the frogs appears perfect with only a few treatments.

BTW, my tifer is back to its old self, eating like a pig, lunging and leaping for food.

Also, I agree with John, do not force feed your frog. He will come around soon after treatemnt begns and feed on his own.