Wart medication to remove hard scabs

Hello, A dermatologist that also is a skin picker, recommended the use of wart removal medicaion, to apply on old hard scabs, that don't want to smooth over. He stated this safe, if used on hard skin, that is re picked over and over. The sore should be completely healed. I read the ingredients in wart medication, and it actually is the same ingredient that is in acne medication. Have any of you ever heard of this treatment? Patricia