In my previous cycles, I have had no issues running arimidex at .25mg EOD. This cycle I am having gyno flare ups, and have needed to resort to my letro standby which I was hoping to never have to use. I was running 750mg/wk of Mast E, and 500mg/wk of Test E. Also 5iu/day hGh. 2.5mg/day of letro took care of any gyno/puffy nips. Despite the masteron and it's supposed anti conversion properties I've still had these issues running .25mg/eod arimidex. Products all obtained by a reliable source here on the boards. After doing a month of letro at 2.5mg/day I feel great! So I titrated down and went to .5mg arimidex a day and still started to get itchy puffy nips and the lump was returning! Product is a popular brand sold by many sources (and I even changed to pharma because I thought it could be fake? with same results). So now I'm back at 2.5mg/day letro and I feel great. This is a really high dose, and when i stopped I got some crazy rebound so I'm scared to stop taking it at this dose. No sexual issues, nothing. I read it takes 60 days to peak in the blood, but my estrogen has not crashed as a result of it's use, at least not yet, and it's been 35 days. Does anybody have any experience with this? My cycle is coming to an end, so I'll be starting PCT shortly, but is it possible that I've become more sensitive towards conversion to estrogen over time? Any advice would help as I've been going around in circles in my own head. Thanks in advance for any help or experience with this.