Patients with atopic dermatitis (AD) have higher rates of skin infections from viruses and bacteria. They also have an impaired innate immune system. Antimicrobial peptides are a component of the innate immune system which are decreased in atopics. In vitro, pimecrolimus has demonstrated its ability to increase antimicrobial peptides. This study will examine the ability of pimecrolimus to increase antimicrobial peptides in vivo in AD patients. Thus, the study will yield a better understanding of the role of pimecrolimus in regulating the immune system in atopics.