My Doctor Prescribed Santyl For A Sore On My Leg,

My doctor prescribed Santyl for a sore on my leg, it is on a old skin graft. It has completely turned it into white dead skin put it will not come off. I used some clobetasol ointment on it and began to loosen it and it started to come off in spots. but I ran out of it and was looking for something over the counter I could use.