After running a heavy cycle of prohormones. Something that I did not think would produce gyno. I experienced it first hand. Little bumps under my nipples. I first noticed sensitivity 2 weeks into my 6 week cycle. Good thing a did some reading and had some tamoxifen citrate on hand. 3 weeks into my PCT and the little bumps are 80% gone. I see why people say to have everything on hand. Wouldn't want to be "that guy" who has bitch tits in the gym.