method used primarily in the practice of rehabilitative medicine to transport charged drug ions across the skin barrier to a therapeutic
level.5 A few studies have established the utility of this means of delivery of vitamin C to effect a clinical improvement in melasma.
16,17 Vitamin C is a negatively charged ion in solution that may be transported into the skin using iontophoresis in the treatment of melasma.2
α-Hydroxy acids, including glycolic acid and lactic acid, have also been used in the treatment of melasma with some benefit.
3-7 One of the authors (M.B.T.) has extensive experience using other α-hydroxy acids, including mandelic and malic acid, in the treatment of melasma. Mandelic acid is an aromatic α-hydroxy acid with the molecular formula C6H5CH(OH)CO2H. Malic acid is an organic compound with the formula HO2CCH2CHOHCO2H.
Both mandelic and malic acid are longer-chain α-hydroxy acids than glycolic or lactic acid and are less likely to cause irritation and PIH than glycolic acid (M.B.T., unpublished data, 2002-2008). Mandelic acid is widely recommended as an over-the-counter therapy for the treatment of melasma.18,19
We evaluated the treatment effect of vitamin C delivered via full-face iontophoresis mask (FFIM) combined with a mandelic/malic acid skin care regimen in patients with melasma or PIH.
We initially evaluated the use of FFIM with vitamin C preparation
in 101 patients with recalcitrant melasma or PIH receiving care at an aesthetic dermatology clinic. Patients verbally consented
to have their data collected as part of this research study. There were no restrictions on the type of skin care products that patients could use for daily skin maintenance.
During the study, it was noted that patients using the FFIM vitamin C therapy and a certain daily skin care regimen consisting
of a 6% to 10% mandelic/6% to 10% malic acid (M2; MCK Laboratories, Salt Lake City, UT) showed the greatest sustained improvements in pigmentation. This report describes the outcomes
for the 35 patients who used the FFIM vitamin C therapy in conjunction with the mandelic/malic acid skin care regimen.
Treatment and Assessment
After screening and informed consent, patients were instructed
in proper application and use of the FFIM and vitamin C preparation containing 20% ascorbyl glucoside. FFIM vitamin C treatments consisted of a 1-hour application 3 times each week for 1 to 2 months.
Photos were taken of each subject before and after (ie, last follow-
up appointment) treatment using the Canfield Mirror Suite photographic system (Canfield Scientific, Inc, Fairfield, NJ) and a Nikon D-80 digital camera (Nikon Corporation, Tokyo, Japan). Photographs
were judged by 4 independent observers, who graded the improvement of melasma and PIH on the following quartile scale: 1 = slightly better, 2 = moderately better, 3 = much better, and 4 = clear or almost clear. Response to treatment was also graded with the Melasma Area and Severity Index (MASI), which assesses severity in each of the 4 regions (forehead, right malar region, left malar region, and chin) as a percentage of the total area of involvement (A), darkness (D), and homogeneity (H).20
Full-Face Iontophoresis Mask (FFIM)
The FFIM utilized in this study was the Cosmion Iontophoretic Rejuvenating Facial Mask (Cosmion LLC, Salt Lake City, UT; Figure 1). This FFIM is constructed of medical-grade materials,