Impact of order of application of moisturizers on percutaneous absorption kinetics: evaluation of sequential application of moisturizer lotions and azelaic acid gel 15% using a human skin model.

The medical management of rosacea increasingly has involved not only the appropriate selection of topical medication but also patient education and specific recommendations regarding appropriate skin care. The recognition that epidermal barrier dysfunction and transepidermal water loss (TEWL) play a pathophysiologic role in rosacea and that skin moisturization may help to mitigate signs and symptoms of the disease has led to a deeper appreciation of the importance of proper skin care in the treatment of rosacea. Data from a percutaneous penetration study performed using human skin suggest that any of the tested moisturizer lotions may be applied either before or after azelaic acid gel 15% without a major change in the percutaneous absorption profile of azelaic acid.