I was diagnosed with pv 2 years ago was put on hu and low dose asprin. Blood work every month, when count went up it was phlebotomy. At times I was able to go 3 month without no tests until a few month ago my red blood count was going down so had an endoscopy done. I had developed iron defiency anemia and was put on iron pills, taken off of hu ,asprin. now count has come back up so no more iron pills and still taking baby asprin. I found that hu can cause anemia, asked the dr about taking it again and he said wair till next month blood work to see.