I use Dapsone for my dermatitis herpetiformis. Was not an issue in the beginning of diagnosis. Once I did the covid vaccine it changed and now I cannot stop using the medicine for more than 24 hours or it flares up with a vengeance. Then it takes just over two weeks for the med to get it back under control. My dermatologist was able to identify and treat it, fortunately for me I was her third patient with dermatitis herpetiformis to have a reaction post vaccine. Trial and error with other antibiotics and a ton of steroids prior to this med. Not cheap and can be problematic for liver and pancreas.