A variety of products are advertised both on television and in print that claim to reduce under-eye circles. It is hard to generalize, but under-eye circles are remarkably resistent to treatment.
Q Are there any effective treatments for under-eye circles?
The real question is, do they work? It is hard to generalize, but under-eye circles are remarkably resistant to treatment.
Darkening of the lower eyelid may also be due to vascular dilation and venous sludging around the eye. This occurs in persons with multiple inhaled allergens and can be partially improved by the use of antihistamines, such as over-the-counter Zyrtec (cetirizine hydrochloride, Pfizer) or prescription Xyzal (levocetirizine dihydrochloride, Sanofi-Aventis).
Another cause of lower eyelid pigmentation is shadowing resulting from deep-set eyes and the shadow of the superior orbital ridge on the lower eyelid. This type of pigmentation is best treated cosmetically with light-reflecting pigments placed beneath the eye.
Thus, there are some treatments that may be effective for under-eye circles, but it is hard to know whether the products advertised in the popular press actually work.
Q How do haircare products work that claim to prolong hair color? Doesn't the color disappear with new hair growth?
A The newest category of haircare products includes those products that are designed to prolong hair color. However, this does not mean that the hair color will somehow transfer to the new growth. Color-prolonging products work only on the colored hair and prevent fading of the dyed hair. This can be accomplished by preventing removal of the hair dye by shampooing or by preventing UV damage of the hair color.
Permanent hair coloring works by creating new color molecules within the hair shaft through an oxidation/reduction reaction. These new color molecules remain in place until washed away by shampooing, which slowly removes the color and results in color lightening. Shampoos with high detergency will remove more of the color, while milder cleansing shampoos will remove less. Thus, shampoos to prolong hair color possess mild surfactants and provide hair conditioning.
In addition, color-prolonging products contain sunscreen. The sunscreen shields the dyed color molecules from UV rays, which prevents photodegradation of the dye. The pheomelanins are more resistant to UV degradation than the eumelanins, accounting for the tendency of both blond and brunette dyed hair to fade to a reddish color. Sunscreens are probably the most important ingredient in products designed to prolong hair color.
Zoe Diana Draelos, M.D., is a Dermatology Times editorial adviser and consulting professor of dermatology, Duke University School of Medicine, Durham, N.C. Questions may be submitted via e-mail to firstname.lastname@example.org