Acne is the most common skin disease in adolescent boys & girls. Under androgenic stimulation the sebacious follicles of face and neck produce excess of sebum and get colonized by bacteria. Bacterial lipases produce fatty acids which irritate the follicular ducts causing retention of secretions and hyperkeratosis - 'comedones' are formed which may rupture into the dermis causing inflammation and pustulation. Used almost exclusively for acne are benzoyl peroxide & retionic acid (all trans vitamin A acid, tretinoin).
