Hi Ana,
Eric had Sarcoidosis many years ago and takes Prednisone 3x/wk. He is also having issues of lingering bookend sores on either side of his tongue near the back teeth. There is some improvement but they are painful. His team of doctors reviewed his medical history and discussed his issues and feel the Prednisone may be the cause of such slow healing. I don't know if this applies to your husband but maybe something to discuss with his doctors. Good luck!