It usually causes some hemolytic anemia which needs to be followed with blood tests. Most people lose 1-2 gram of hemoglobin, an amount most people don't notice. It also can convert some hemoglobin to methemoglobin, but again not usually to a significant degree. Some people with DH are controllable with fairly low doses which cause less of this. Most patients don't report noticing any difference, but the potential for one is there. Those with G-6-PD deficiency are at higher risk, although I have one such on Dapsone and doing well. Dapsone also rarely causes aplastic anemia. You have to follow blood counts closely at first, but eventually I just check counts annually on most folks. Problems that arise, other than aplastic anemia, should reverse fairly quickly with lower dosage or discontinuation.
OK, thanks! I might look into it further if symptoms do not continue to decrease.