Topical Rosacea Therapy: The Importance of Vehicles for Efficacy, Tolerability and Compliance
June 2011 | Volume 10 | Issue 6 | Original Article | 627 | Copyright © June 2011
J. Mark Jackson MDa and Michelle Pelle MDb
aUniversity of Louisville, Division of Dermatology, Louisville, KY bMedDerm Associates, San Diego, CA; Division of Dermatology, University of San Diego Medical Center, San Diego, CA
Many topical medications are available for the treatment of papulopustular rosacea. While treatments contain metronidazole, azelaic
acid, or sodium sulfacetamide-sulfur as the active ingredient, the composition of the vehicle formulations varies widely. These vehicles
come in gels, creams, lotions and foams; some ingredients are common to many vehicles, while some vehicles contain unique
ingredients designed to optimize skin penetration and delivery of the active drug to its target. Vehicles can also influence tolerability,
which is always a concern in patients with heightened skin sensitivity, and compliance, which is typically lower for topical treatments
than oral treatments. Ideally, the vehicle of any rosacea treatment should enhance drug delivery, be nonirritating and be easy to use.
Ingredients that help repair barrier function are also desirable. This review will focus on the key components of the vehicles from
the most commonly used topical therapies for papulopustular rosacea and how vehicle formulations influence the delivery of active
ingredient, skin barrier repair, tolerability and compliance.
J Drugs Dermatol. 2011;10(6):627-633.
Rosacea is a common facial disorder affecting approximately
16 million people in the United States.1 The
facial skin of patients with rosacea is characterized by
persistent erythema, visible blood vessels and often papules
and pustules.2 Rosacea sufferers frequently experience skin
sensitivity characterized by physical discomfort, burning sensation,
facial itching, stinging and swelling.3 The lactic acid test
involving application of a solution of lactic acid to the skin and
assessing the subject's reaction is a validated test for determining
skin sensitivity. Approximately 75 percent of patients with
rosacea have a positive reaction to this test compared with <20
percent of normal subjects,4 demonstrating the prevalence of
sensitive skin among rosacea sufferers. There are four main
subtypes of rosacea: erythematotelangiectactic, papulopustular,
phymatous and ocular.5 Available topical treatments are
indicated for the treatment of papules, pustules and erythema.6
Topical medications comprise a major component of therapy for
papulopustular rosacea. Currently, only one oral medication is
approved by the Food and Drug Administration for the treatment
of papulopustular rosacea, a subantimicrobial dose of doxycycline
(Oracea®). In contrast, there are many topical medications
to choose from that vary in active ingredient and vehicle, providing
dermatologists with a wide array of treatment options.
Ideally, treatment should not only deliver the active ingredient
to its site of action but should not further irritate the skin, and
medications that are potentially acnegenic should be avoided.
Formulations that calm and soothe the skin are preferable. Emollient
and barrier repair ingredients are important, as these may
help repair inherent barrier dysfunction.
Other features that are important when choosing a therapy are
its ease of application and its effect on the appearance of the skin
when used with the patients' regular skin care routines, particularly
the application of cosmetics. The ease of application and
appearance of both the medication and patients' usual cosmetic
regimens have been shown to influence patients' ratings of their
overall appearance.7 Ideally, topical therapies should be well tolerated
on oily and/or dry skin, as many patients display findings
of both. A vehicle that is tolerated on both skin types allows for
more flexibility of application.
It has been suggested that the vehicle of a topical therapy may
account for 50 percent to 75 percent of its efficacy.8 A vehicle
must allow penetration of the active ingredient, without damaging
the skin barrier. It must deliver the correct dose, while being
easy to use and well tolerated. This review will focus on commonly
used topical therapies for papulopustular rosacea and the
key components of their respective vehicles that influence the
delivery of the active ingredient and repair of the skin barrier,
and maximize tolerability. How these formulations are accepted
in clinical practice will also be discussed.
Topical Rosacea Treatments and Their Vehicles
Three main active ingredients are found in topical rosacea
therapies: metronidazole, azelaic acid, or sodium sulfacetamide-