Metronidazole, azelaic acid, ivermectin--these are just some of the most recommended treatments for the rosacea. But did you know that the effectiveness of these topical medications can be boosted by the addition of oral antibiotics?
Usually reserved for patients with severe or refractory rosacea, studies have shown the benefits of combining a short course of antibiotic therapy with administration of topical medications as an initial treatment. So how exactly does it work?
Anti-inflammatory > anti-microbial
When we think of antibiotics, we think of microbe control. So if oral antibiotics work on rosacea, that must mean that bacteria play a role in the pathogenesis of the disease…right?
The easy answer is: we’re not exactly sure. Research shows that the skin microbiome of rosacea patients differs from that of healthy controls, in terms of the classes of bacteria present and which bacteria are predominant (Kim, 2020). The implication of these findings is still unclear, but we know that there is no one single cause for rosacea. The pathogenesis of this condition involves a complex interaction of many factors, and bacterial infection is just one of them.
The most convincing evidence of this? The fact that rosacea can be treated with medications that have no to little antimicrobial action. Metronidazole, azelaic acid, and other evidence-based rosacea therapy work primarily because of their anti-inflammatory action (Rivero and Whitfeld 2018).
So if bacteria isn’t a major cause of rosacea, why do we use oral antibiotics to manage it?
This is because oral antibiotics also possess anti-inflammatory properties. Tetracyclines, the class of antibiotics most often prescribed for rosacea, are known to inhibit the activity of neutrophils, pro-inflammatory cytokines, and matrix metalloproteinases; reduce oxidative damage to cells in the skin; and help control vasodilation--all of which are crucial to the development of a inflammatory response (Nagler and Del Rosso, 2019; Schaller et al., 2019). By disrupting this process, you can effectively prevent the hallmarks of inflammation: redness, itchiness, dryness, and stinging.
Using anti-inflammatory dosing
The magical anti-inflammatory (and therefore, anti-rosacea) effects of antibiotics may make you want to down an entire bottle, but it is important to remember the reasons why oral antibiotics are so carefully regulated. Using the inappropriate dosage has many effects, the most serious of which are phototoxicity or increased sun sensitivity, dysbiosis, or a disruption in the beneficial flora and fauna of your body, and the development of antimicrobial resistance, which is a looming public health concern.
Luckily for rosacea patients, the anti-inflammatory properties of antibiotics are still exhibited in doses lower than what it takes to affect bacteria. In addition, modified release formulations have been developed especially for rosacea patients, in order to decrease the risk of dysbiosis, antimicrobial resistance, and other adverse side effects (Zhang et al., 2021).
Two randomized phase III clinical trials found that once daily intake of doxycycline at sub-microbial doses significantly reduced the number of inflammatory lesions and induced more improved and higher rates of facial clearness in patients with moderate to severe papulopustular rosacea (Del Rosso et al., 2007).
While it has been proven to be effective as monotherapy, oral antibiotics are most commonly used in combination with topical medications as a means to get acute flare-ups under control (Cowley, 2013; Rivero and Whitfeld, 2018). When symptoms subside, or at most after 12 weeks, oral antibiotic administration is stopped and topical treatments are continued as maintenance therapy.
This content is for general information only and is not a substitute for medical advice.
References:
Cowley N. 2013. Treatment options in the management of rosacea. Prescriber. https://wchh.onlinelibrary.wiley.com/doi/pdf/10.1002/psb.1113
Del Rosso, James & Brantman, Sam & Baldwin, Hilary. (2022). Long‐Term Inflammatory Rosacea Management with Subantibiotic Dose Oral Doxycycline 40 mg Modified‐release Capsules Once Daily. Dermatologic Therapy. 35. 10.1111/dth.15180.
Kim, H.S. Microbiota in Rosacea. Am J Clin Dermatol 21, 25–35 (2020). https://doi.org/10.1007/s40257-020-00546-8
Nagler, A. R., & Del Rosso, J. (2019). The Use of Oral Antibiotics in the Management of Rosacea. Journal of drugs in dermatology : JDD, 18(6), 506.
Rivero, A. L., & Whitfeld, M. (2018). An update on the treatment of rosacea. Australian prescriber, 41(1), 20–24. https://doi.org/10.18773/austprescr.2018.004
Schaller, M., Schöfer, H., Homey, B., Gieler, U., Lehmann, P., Luger, T. A., Ruzicka, T., & Steinhoff, M. (2016). State of the art: systemic rosacea management. Journal der Deutschen Dermatologischen Gesellschaft = Journal of the German Society of Dermatology : JDDG, 14 Suppl 6, 29–37. https://doi.org/10.1111/ddg.13141
Valentín, Sheila & Morales, Adisbeth & Sánchez, Jorge & Rivera, Abimael. (2009). Safety and efficacy of doxycycline in the treatment of rosacea. Clinical, cosmetic and investigational dermatology. 2. 129-40. 10.2147/CCID.S4296.
Zhang, H., Tang, K., Wang, Y. et al. Rosacea Treatment: Review and Update. Dermatol Ther (Heidelb) 11, 13–24 (2021). https://doi.org/10.1007/s13555-020-00461-0
