Two studies show that emollient creams to relieve the symptoms of eczema make the condition worse

Aqueous cream BP is currently the most widely prescribed emollient for the treatment of eczema and other dry skin conditions, even though it was originally only used as a wash product. It is meant to moisturise the skin, improving flexibility and preventing cracking.

A study by the University of Bath’s Department of Pharmacy & Pharmacology found that when healthy volunteers applied the cream to their forearms daily for a period of four weeks, the thickness of the stratum corneum (the protective outer layer of skin) was reduced by more than 10%. The researchers suggest that using this cream would have an even more dramatic effect on damaged skin such as that found in eczema.

They commented:
‘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.’

They suggest that it might be better for eczema patients to use oil-based ointments on damaged skin.

M. Tsang, R.H. Guy. Effect of Aqueous Cream BP on human stratum corneum in vivo. British Journal of Dermatology, 2010

Edited to add:
Research published in the British Journal of Dermatology shows why aqueous cream can make the condition worse and increase the peeling and inflammation of the skin. The study, carried out at the School of Pharmacy at the University of London Skin Research Centre, showed a clear difference between treated and untreated skin. Treated areas became more inflamed and prone to peeling, lost moisture and the skin cells decreased in the size and maturity.

The aim of the study was to investigate changes in normal skin after a 28-day application of Aqueous Cream BP. The forearms of six healthy female volunteers were treated, and at the end of the 28 days the test areas were taped-stripped and various measurements recorded.

The results reported rapid, minimally invasive measures of the effects of the cream at the cellular and molecular level of the skin. One of the causes of this is the protease enzyme, which break down skin proteins. The detergent sodium lauryl sulphate also causes many of the issues identified in the study, yet its presence in the cream is not often clearly indicated.

Source: Wiley online library.

See also Micki Rose’s article – Thinny Skinnies.

Octocber 2010, with additions in May 2011

Click here for more research on the management of eczema

For links to skin and personal care products click here.