Hormones are the  best  examples.  Since  sebaceous glands are predominantly under endocrine control (in particular that  of androgens) it is not surprising that testosterone can induce acne in eunuchs, females and pre-adolescent  children.  Gonadotrophins, which may be given in certain pituitary disorders, can indirectly aggravate acne by a direct stimulating  effect  on the testosterone production. Anabolic steroids are masculinizing and so can aggravate acne, especially in females. This is a problem, for example, in treating with anabolic steroids  female patients who have familial angiooedema.

  Some  power  athletes  are  also  known to  selfadminister large  doses of  androgenic anabolic  hormones.  This can precipitate acne and increase sebum output. Oral  and topical corticosteroids and adrenocorticotrophic hormone (ACTH) can  also produce iatrogenic  acne.  The  clinical picture  so  produced by corticosteroids  tends to be  much more monomorphic than that seen in ordinary  acne, but the lesions  can consist of comedones  or superficial  papules and  pustules . Nodules, cysts  and scars are  rare unless the patient  has an underlying  predisposition  to   acne.  Flat  follicular hyperkeratotic  lesions may  also be  seen. Steroid acne which is dose-dependent rarely occurs before puberty.

  The mechanism of steroid acne is  different  in part from  conventional acne. The steroid produces focal degeneration of the follicular epithelium; this accounts for the inflammatory papules. It is said that the comedones which follow are probably due to a sensitizing effect on the epithelium by the steroid to the irritant properties  of  the  native  comedogenic  substance, sebum.39 Topical steroids have been reported either to increase the  number of ductal  P. acnes or have no effect. It is not really known whether or not steroids influence acne inflammation; such a study is necessary.