Drug treatment of photoaged skin.

Abstract

Although the prevention of skin aging is a holy grail of the cosmetic and pharmaceutical industries, this venture may be misplaced. The predominant clinical and biochemical features of aged skin are mostly attributable to photoaging rather than chronology. For instance chronic sun exposure is the major determinant of age spots (actinic lentigines) and wrinkles. Surgical approaches to the treatment of photoaging include face-lift, dermabrasion, chemical peeling, collagen and botulinum toxin injections, and laser re-surfacing. These approaches all have benefit and improve the clinical features of facial photoaging. Drug or pharmaceutical prevention and treatment of photoaged skin is still in its infancy. The main pharmaceutical approach to prevention of photoaging lies in the assiduous use of sunscreens. Recent evidence points to the importance of ultraviolet A (UVA) radiation as well as ultraviolet B (UVB) radiation in the aetiology of photoaging and thus the need for sunscreens that block both UVB and UVA. Drug treatment of photoaged skin can be categorised as antioxidants, alpha-hydroxy acids and topical retinoids. Of these 3 approaches only topical retinoids, particularly tretinoin (all-trans retinoic acid), have a well documented ability to repair photoaged skin at the clinical, histological and molecular level. Furthermore, the use of topical retinoids may actually prevent photoaging. The current interest in pharmaceutical modulation of the photoaging process has attracted considerable research into the mechanisms of photoaging and cutaneous aging. It is likely that treatment for, or prevention of, the chronological aging process may result from such research.