New York—A novel over-the-counter topical protectant
lotion offers a steroid-free approach to prevention and management of irritant contact dermatitis, Dr. Hongbo Thai reported in a poster
presentation at the American Academy of Dermatology's Academy '99.
Proteque, which combines dimethicone with botanically
derived anti-inflammatory ingredients and an antimicrobial agent called Irgasan, can prevent contact dermatitis resulting from continuous or
repeated exposure to irritant chemicals, said Dr. Thai of the department of dermatology, University of California, San Francisco.
In a study funded by the manufacturer, Proteque International, Dr. Zhai tested the product against vehicle alone in 12 healthy
while subjects, aged 30-55 years. They were experimentally exposed to the common irritant, sodium lauryt sulfate (SLS). The flexor surface
of the subjects' left and right forearms were randomly assigned in a blinded l~sbion to be pretreated with either the active Proteque lotion
or inactive vehicle.
Thirty minutes later, 0.2 ml of 0.5% SLS were applied using a polypropylene chamber, which was left in
place for 24 hours. On each forearm, the investigators also applied the SLS to an area of unprotected skin, to facilitate comparison of the
ensuing reactions.
The outcomes measures included transepidermal water loss (TEWL), skin color, and cutaneous blood flow
volume. IX Thai also used a clinical visual scoring scale to rate the contact dermatitis. Assessments were made at baseline, and days 2,3,4,
and 5 following application of the irritant.
The extent of irritant contact dermatitis and objective measurements of TEWL
were both decreased significantly in the Proteque-treated areas, compared with the non-treated and vehicle-treated sites. There
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were no differences between the sites in terms of cutaneous blood flow volume or skin color.
Dr. Zhai noted that the study was small and the findings preliminary. But he believes the reduction of TEWL, and degree of
irritation indicates that Proteque does provide a considerable degree of benefit in preventing dermatitis from direct chemical exposure. Dr.
Zhai said he had no financial interest in this product. This protective function, which is the FDA-approved indication for Proteque, is
attributed largely to the dimethicone, a silicone derivative that provides a relatively impermeable protective layer against water and
commonly encountered chemicals such as formaldehyde, said Fred Brachman, president of the Raleigh, N.C.–based company that makes and markets
the product. "Dimethicone seals in moisture and keeps out irritants," he told SKIN & ALLERGY NEWS.
The recommended
treatment regimen for protecting against external chemical irritants is to apply the lotion, 2-3 times per day, after washing and drying the
area to be treated.
Each application is generally protective for 4-8 hours, or 15-20 washings, depending on which comes
first. On the face, one daily application is usually sufficient.
It is important to stress to patients not to overuse the
product. Beyond thrice daily application, Proteque can cause a drying or skin-stiffening effect.
The product also contains
extract of Lonicera japonica (honeysuckle), aloe vera, and tocopheryl acetate, a nonirritant form of vitamin E. Mr. Brachman said each of
these ingredients has anti-inflammatory and antioxidant properties.
The final key ingredient is Irgasan DP 300, a new
formulation of the antimicrobial 5% triclosan, developed by Ciba specialty chemicals.
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