Percutaneous absorption of hydroquinone in gumans: effect of 1- dodecylazacycloheptan-2-one (Azone) and the 2-ethylhexyl ester of 4- (dimethylamino) benzoic acid (Escalol 507).
Bucks-DA; McMaster-JR; Maibach-RH
Departments of Dermatology and Pharmaceutical Chemistry, Schools of Medicine and Pharmacy, University of California, San Francisco, California, 1987 Dec; :1-20
The effects of a penetration enhancer, 1-dodecylazacycloheptan-2-one (Azone) and a sunscreen, the 2-ethylhexyl ester of 4-(dimethylamino)- benzoic-acid (Escalol 507) on the percutaneous absorption of hydroquinone (123319) were studied. Volunteers each received a single 100 microliter dose of carbon-14 labeled hydroquinone module by topical application to forehead skin. Module 1 contained Azone and Escalol-507, module 2 contained Azone, module 3 contained Escalol-507 and module 4 contained no Azone or Escalol-507. Average percutaneous absorption of hydroquinone as estimated from the urinary elimination data was 35, 66, 26, and 57 percent for modules 1, 2, 3, and 4, respectively. Peak elimination was noted within the first 12 hours and elimination was complete within 5 days from application. Escalol-507 (3 percent by weight) significantly inhibited the absorption. Azone (0.5 percent by weight) did not significantly increase absorption either alone or with Escalol-507 present. The authors suggest that if Azone were used at higher concentrations or in a different vehicle system, the findings might be different.
NIOSH-Grant; Dermatitis; Skin-exposure; Skin-absorption; Antioxidants; Pharmaceuticals; Humans
Pharmacy University of California 926 Medical Sciences Building San Francisco, Calif 94143
Final Grant Report
NTIS Accession No.
Departments of Dermatology and Pharmaceutical Chemistry, Schools of Medicine and Pharmacy, University of California, San Francisco, California
University of California San Francisco, San Francisco, California