Deca is a derivative of 19-Nortestosterone. One of the most popular steroids and easiest to obtain (as well as being the most counterfeited). Deca is excellent for producing gains in size and strength. It's used to cutting and bulking up and can be stacked with virtually all steroids. This drug reduces dramatically the time needed for recuperation after workouts. It's easy to detect and can be found on drug tests up to a year after the injection.
"Deca dick" is a side effect, and can be prevented or at least minimized with anti-estrogens. This usually occurs when the user goes off steroids. When first used, steroids increases sexual interest and the heightened frequency and duration of erections, however eventually the opposite happens and no erections can be produced. This is all because of estrogen, not the steroids themselves.
------------------
Complex problems have simple, easy to understand, wrong answers.