The first time I cycled, when I came off I had sore nipples and I attributed it to estrogen rebound. I recently started trt, at 400mgs of test and 150 of deca I pretty bad gyno so I started with letro at 2.5 then worked my way down. Now I wanted to leave some estrogen for binding reasons so I switched to anatrozole. Holy shit, the next day or two I had a lump under my left nipple I thought was going to pop out, I couldnt sleep on my stomach, couldnt put my chest up against a machine to do rows. Now my question is, did the letro totally stop my estrogen production, then when I stopped using it, it mass produced? I also did a shot of HCG that day and upped my GH. Could all of this combined caused this, I wish I took a picture, it was unreal. Then to add insult to injury, when I saw my doc for blood work, he looked at it and grabbed it like it was his first tittie he ever got, man he's lucky I like him so much!
If I had to guess, I would say it was a combination of incomplete estrogen suppression and very low androgen levels. There really isn't an estrogen rebound post cycle per say, but rebound estrogenicity caused by an imbalance of androgens (suppressed) and estrogens (suppressed, but still fed by adrenal sources).
That sounds right, but the second time with the huge lump my blood levels were stabalized, I had been on the cyp and deca for almost 2 months. Does that not matter?
I sort of had the same prob on my last cycle. I was afraid to start the Letro due to cleaning out all my estrogen, but I didn't ramp it. I used it at 2.5 MG ED for 1.5 weeks then I think half that does exactly for another 1.5 and I was fine. The small lumps cleared and the puffiness of the nipples went away. I didn't feel that I had a rebound effect after I stopped the Letro either. So I don't know bro.
Like Nandi said, estrogen levels parallel Testosterone levels. Low test = low estrogen. There might be some "imbalance" issues though like Bill said.