The current clinical guidelines for the treatment of atopic dermatitis advocates the application of moisturizers as an integral part of the treatment of patients with AD (based on level I evidence) and there stands strong evidence on its use reducing disease severity and the need for pharmacologic intervention.

The colloidal oatmeal treatment is used for numerous dermatologic diseases, due to its wide range of phytochemicals that contribute to its wide-ranging function and clinical use is known for ages.

Its mechanism of action includes- direct anti-inflammatory, anti-pruritic, anti-oxidant, anti-fungal, pre-biotic, barrier repair properties, and beneficial effects on skin pH. This preparation has especially benefitted patients with atopic dermatitis. 

A paper published by Allais B. and Friedman A. discusses the history of colloidal oatmeal, basic science, mechanism of action, and its clinical efficacy in the treatment of atopic dermatitis.

Basic oat science

Composition of colloidal oatmeal-

• sugars and amino acids (65%),
• proteins (15–20%),
• lipids (11%), and
• fibre (5%). 

Phytochemicals in oats-

• phenolics,
• β-glucans,
• lignans, avenanthramides,
• carotenoids,
• vitamin E, and
• phytosterols. 

Phenolics like ferulic acid and caffeic acid act as strong antioxidants, additionally ferulic acid also has UV absorbing properties. Phenolics like Flavonoids are too capable of absorbing ultraviolet A light from 320–370 nm. 

Among the wide range of minerals and vitamins present in oats, vitamin E is the most important as it is a naturally occurring antioxidant that protects against oxidative stress, inflammation, and photo-induced ageing.

Both lesional and non-lesional skin in AD undergoes xerosis, barrier abnormalities, and reduced content of ceramides. The disrupted skin barrier causes much transepidermal water loss, gives entry to the irritants and allergens from the environment leading to itching via cytokine release and inflammation. Avenanthramides in colloidal oatmeal decrease inflammation, thus rendering an anti-itch effect, via reducing the release of pro-inflammatory cytokines and can reduce scratch up to 40%.

Lipids and fatty acids contents in colloidal oatmeal also offer barrier protection and help to reestablish the stratum corneum in atopic dermatitis, which can be appreciated by reduction in the levels of ceramides (a vital stratum corneum lipid). 

Thus the authors advocated the use of colloidal oatmeal in the management of AD and other varieties of dermatoses through their paper.

Source: Allais, B, Adam Friedman A. Action, and Clinical Efficacy in the Treatment of Atopic Dermatitis. Journal of Drugs in Dermatology, 2020;19(10).