Microbial catabolism of phytosterol side chains yields C-19 steroids, C-22 steroids, and 17-ketosteroids (. precursors to adrenocortical hormones and contraceptives ).     The addition and modification of functional groups is key when producing the wide variety of medications available within this chemical classification. These modifications are performed using conventional organic synthesis and/or biotransformation techniques.  
Prescriptions written for topical steroids should include explicit instructions about where and how often to apply the preparation, and the body areas where use must be avoided. Pharmacists should ensure these directions are included on the dispensing label. Prescribers should bear in mind that patients may keep unused or leftover corticosteroid skin preparations for some time after they are prescribed and thus forget the original indication or instructions for use. The prescribing of unnecessarily large quantities should be avoided. Patients should be warned not to share their topical steroid preparation with other people as this may result in unsafe application to unsuitable areas such as the face, as well as the potentially inappropriate treatment of undiagnosed skin conditions.
STEROIDS is an international research journal devoted to studies on all chemical and biological aspects of steroidal moieties. The journal focuses on both experimental and theoretical studies on the biology, chemistry, biosynthesis, metabolism, molecular biology, physiology and pharmacology of steroids and other molecules that target or regulate steroid receptors. Manuscripts presenting clinical research related to steroids, steroid drug development, comparative endocrinology of steroid hormones, investigations on the mechanism of steroid action and steroid chemistry are all appropriate for submission for peer review. STEROIDS publishes both original research and timely reviews. For details concerning the preparation of manuscripts see Instructions to Authors, which is published in each issue of the journal.