Anabolic steroids can cause the development of acne. However, the extent to which it is experienced can be due to a number of varying factors, with the particular steroids and exact dosages used being primary. The skin´s sebaceous glands have a particularly high affinity to Dihydrotestosterone, which is an androgen the body naturally produces from testosterone via the enzyme 5-alpha Reductase. Increased sebaceous gland activity promotes oily skin which can combine with bacteria and dead skin (normal wear and tear) eventually causing pores to become clogged more quickly than the body can cleanse them. This of course, is preventable by using only particular steroids, cleansing the skin regularly, and perhaps using a topical anti-androgen.
This is the scenario: a guy, say age 21, becomes serious about gaining muscle. He’s 5′ 10″, 7″ wrists, 9″ ankles, average genetics for muscle size-and-proportioned. He’s played sports, but never done more than an occasional resistance workout. Now, he begins a good training-eating-and-resting program. With his genetics, he has the potential for naturally gaining 45 pounds of lean mass if he stays consistent with progressive training/proper eating for a continuous 3 to 4 years.
But, about three months after beginning his training, he starts taking steroids. He does three steroid cycles in the following 18 months, and includes proper post-cycle therapy. That entire time, he’s continuing to consistently train and eat properly. Before the end of two years, he’s gained 45 pounds of lean mass (which with steroids, by the way, is not necessarily typical but neither improbable). At that point, he permanently quits using steroids, but he does continue properly training and eating for another two years. At the end of four years, he carries the same 45 pounds of lean mass.