Evaluation of the Inhibitory Effects of Topical Ivermectin on Markers of Rosacea Specific Inflammation.

This study will assess the role of topical Ivermectin 1% cream and its effect on protease and antimicrobial peptide expression and on the skin microbiome (the microorganisms that live on the skin) in rosacea. This is a single-site 16-week open-label study at University of California, San Diego. The investigators will do this by first measuring serine protease activity and cathelicidin and skin microbiome of all subjects. All subjects will receive Ivermectin topical cream and will be instructed on how to apply it daily for 12 weeks. Participants will return for monthly visits during which their clinical symptoms of facial redness and number of facial papules will be scored, and they will have repeat tape stripping and/or skin swabs. At the end of the study, tape strips and skin swabs will be analyzed to determine serine protease activity and skin microbiome of participants at each of their visits and expression of cathelicidin (LL-37) mRNA. The investigators will then look at changes in serine protease activity and LL-37 expression and skin microbiome over time, and they will also determine whether or not these changes correlate with disease severity.