Efficacy of skin barrier creams (II). Ineffectiveness of a popular "skin protector" against various irritants in the repetitive irritation test in the guinea pig.

A popular "skin protector" consisting of an emulsion-like foam of lipophilic and hydrophilic substances (Marly skin) was evaluated in a previously described repetitive irritation guinea pig model. The product failed to inhibit the irritation due to sodium lauryl sulphate and toluene. In striking contrast to the recommended use, the irritant response of sodium hydroxide was aggravated, as demonstrated by significant differences for all test parameters (clinical score for erythema and scaling, transepidermal water loss, blood flow volume). The results show that protection against chemical irritants may be quite specific and that some formulations may actually be harmful.