Sun Protection Strength of a Hydroquinone 4%/Retinol 0.3% Preparation Containing Sunscreens
April 2006 | Volume 5 | Issue 4 | Original Article | 321 | Copyright © April 2006
Joseph W. Stanfield MS, Steven R. Feldman MD PhD, Jacob Levitt MD
Methods:We tested the sun protection factor of a hydroquinone formulation (Lustra-UltraTM, TaroPharma, Hawthorne, NY) containing avobenzone 3%, and octinoxate 7.5% according to the FDA Sunscreen Monograph on 20 volunteer subjects. We also determined the UVR absorbance spectrum of the preparation.
Results: The mean sun protection factor (SPF) of 21.7 satisfied labeling requirements for SPF 20. The formulation exhibited strongest photoprotection near the wavelengths of peak sun burning effectiveness in the UVB region and maintains significant UVR absorbance through the entire UVA region.
Conclusions: Avobenzone 3% and octinoxate 7.5% provide broad spectrum UV protection. Incorporating these sunscreens into a hydroquinone preparation simplifies the treatment regimen while providing significant photoprotection for patients being treated for dyschromia.