Skin benefits from continuous topical administration of a zinc oxide/petrolatum formulation by a novel disposable diaper.

BACKGROUND: Diaper dermatitis is a common childhood affliction. Aiming to help reduce the prevalence of this problem, we have advanced in our development of a novel diaper that delivers dermatological formulations to help protect the skin from over-hydration and irritation. OBJECTIVE: To determine the clinical benefits of a novel disposable diaper designed to deliver a zinc oxide and petrolatum-based formulation continuously to the skin during use. METHODS: All studies were independent, blinded, randomized clinical trials. Study A was conducted to confirm transfer of the zinc oxide/petrolatum (ZnO/Pet) formulation from the diaper to the child's skin during use. Children wore a single diaper for 3 h or multiple diapers for 24 h. After the use period, stratum corneum samples were taken from each child and analysed for ZnO/Pet. Study B evaluated the prevention of skin irritation and barrier damage from a standard skin irritant (SLS) in an adult arm model. Study C evaluated skin erythema and diaper rash in 268 infants over a 4-week usage period. One half of the infants used the ZnO/Pet diaper, while the other half used a control diaper that was identical except for the absence of the ZnO/Pet formulation. RESULTS: The ointment formulation and ZnO transferred effectively from the diaper to the child's skin during product use. Transfer of ZnO increased from 4.2 microg/cm2 at 3 h to > 8 microg/cm2 at 24 h. Exposure to the formulations directly on adult skin prior to an irritant challenge was associated with up to a 3.5 reduction in skin barrier damage and skin erythema. Greatest reductions were seen for the ZnO containing formulations. Wearing of the formulation treated diaper was also associated with a significant reduction in skin erythema and diaper rash compared to the control product. CONCLUSIONS: The results demonstrated the clinical benefits associated with continuous topical administration of a zinc oxide/petrolatum-based formulation by this novel diaper.

A modified cup scrub method for assessing the antibacterial substantivity of personal cleansing products.

An improved in vivo method for evaluating the antibacterial substantivity or residual effectiveness of bar soaps and other personal cleansing products is presented. The effectiveness of an antibacterial bar soap containing 1.5% 3, 4, 4'-trichlorocarbanilide (TCC) versus its soap vehicle was evaluated under simulated conditions considered optimal for bacterial growth, proliferation, and possible infection. A washout period to clear the skin of any antimicrobial agents previously used was followed by a treatment period in which the subjects washed one of their forearms with the antibacterial soap and the other forearm with the soap vehicle. Either immediately or 24 hours following the final wash, three test sites on both forearms were inoculated with S. aureus and occluded with Hill Top Chamber patches. At intervals of 30 minutes, two hours and five hours, the patches were removed. The bacteria on the skin were harvested using the Williamson-Kligman scrub technique (1,2) to determine the number of surviving CFUs at each time period. The method successfully demonstrated that sufficient TCC had remained on the skin for 24 hours after the final wash to effectively inhibit the growth of S. aureuso on the skin for as long as five hours after inoculation.