Nandrolone can cause erectile dysfunction despite typically increasing sex drive through estrogenic effects.

“and uh nandrolone also have this curious side effect it's colloquially termed Deca dick because uh nandon to cano8 does a substance called Deca um it is the uh is erectile dysfunction approximately caused by the presence of nandrolone and it's curious because nandrolone Ty with their estrogenic effects Elevate sex drive kind of the more estrogen you have to a point the more sex drive you have if you have pres of yeah and so um you're horny but then like little little Billy down there doesn't work as well as he used to or at all”