Moisturising creams may make eczema worse

Using moisturising creams to relieve the symptoms of eczema could make the condition worse, scientists have found.

Aqueous cream BP is the most widely prescribed emollient for the treatment of dry skin conditions. It is used to moisturise the skin, improving flexibility and preventing cracking in the protective outer layer, called the stratum corneum.

But researchers at Bath University found that the cream also causes thinning of healthy skin after being used for weeks.

They say the cream contains a detergent, called sodium lauryl sulphate (SLS), which can increase the permeability of the skin barrier and cause irritation.

When healthy volunteers applied the cream to their forearms every day for four weeks, the thickness of the stratum corneum was reduced by more than ten per cent.

The researchers suggested that using this cream would have an even more dramatic effect on damaged skin such as that found in eczema, and people with eczema should opt for oil-based products instead.

Professor Richard Guy explained: “The skin has a protective barrier layer of lipids, around one eighth the thickness of a sheet of paper, that stops chemicals from getting into the body and keeps moisture in.

“SLS is a detergent used to mix oils into water-based moisturisation creams to give a nice creamy texture. It’s also used widely in shower gels and other cosmetics.

“Our study has found that rubbing aqueous cream containing SLS into the skin thins this protective barrier, making the skin more susceptible to irritation by chemicals.

“So to use this cream on eczemous skin, which is already thin and vulnerable to irritation, is likely to make the condition even worse.”

The findings are published in the British Journal of Dermatology.

This article was published on Tue 19 October 2010