A hydroquinone formulation with increased stability and decreased potential for irritation.
BACKGROUND
Long-term treatment with a high-strength hydroquinone (HQ) cream (usually 4% HQ) is the mainstay therapy for hyperpigmentation disorders. Instability and high potential for irritancy hinders patient compliance. A new 4% HQ preparation has been designed with an innovative antioxidant for stability and a biomimetic of an herbal extract for skin calming.


OBJECTIVE
To investigate the activity, stability, and irritancy of a new HQ cream.


METHODS
To evaluate the new HQ cream in comparison with commercial 4% HQ creams for stability by temperature stress test, for irritancy by repeated-insult patch test on human subjects, and for lightening effect using the MelanoDerm B skin equivalent model.


RESULTS
The new HQ is more resistant to browning and shows less irritancy than three commercially available 4% HQ products. It has comparable bleaching effect with faster onset than a 4% HQ product containing 0.05% tretinoin and 0.01% fluocinolone acetonide.


CONCLUSIONS
Based on its improved stability, lower irritancy, and activity in skin lightening, the new approach to the formulation of 4% HQ may improve therapeutic outcomes by improving patient compliance to dosing.
Smiles
Kenneth A
KA
AGI Dermatics, Freeport, NY, USA. ksmiles@agiderm.com
Dong
Kelly K
KK
Canning
Matthew T
MT
Grimson
Roger
R
Walfield
Alan M
AM
Yarosh
Daniel B
DB
D000328:Adult; D000470:Alkaloids / Q000008:administration & dosage; D000975:Antioxidants / Q000008:administration & dosage; D002478:Cells, Cultured; D017453:Dermatitis, Irritant / Q000209:etiology*; D003879:Dermatologic Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry; D004338:Drug Combinations; D004355:Drug Stability; D004880:Ergothioneine / Q000008:administration & dosage; D005260:Female; D006801:Humans; D006873:Hydroquinones / Q000008:administration & dosage* / Q000009:adverse effects / Q000737:chemistry; D017495:Hyperpigmentation / Q000188:drug therapy*; D008297:Male; D008543:Melanins / Q000096:biosynthesis; D008544:Melanocytes / Q000187:drug effects* / Q000378:metabolism; D011799:Quinazolines / Q000008:administration & dosage; D023422:Skin Irritancy Tests; D018709:Statistics, Nonparametric
D000470:Alkaloids; D000975:Antioxidants; D003879:Dermatologic Agents; D004338:Drug Combinations; D006873:Hydroquinones; D008543:Melanins; D011799:Quinazolines; D004880:Ergothioneine; C031927:hydroquinone