My Daughter Has Been Taking Subutex For Several Months And

My daughter has been taking subutex for several months and her feet, ankles and legs are hugely swollen, hot, red and sometimes blotchy. She stopped the subutex a month ago because of this but to date the swelling has not receded. Is it now cellulitis? What can we do. Her primary doctor was not familiar with subutex and does not seem concerned but I am very concerned as her ankles, feet and legs to the knee are HUGE.