Chronic dry skin diseases such as psoriasis are characterised by a compromised skin barrier function, leading to increased transepidermal water loss and the clinical manifestations of dryness, scaling, and inflammation. In this context, emollients and a consistent general skincare routine play a crucial role in managing the symptoms, supporting the skin barrier, and improving the overall quality of life for affected individuals.
The foundation of healthy skin lies in the integrity of the epidermal barrier, primarily the stratum corneum. In psoriasis, this barrier is disrupted, leading to a cycle of dryness and inflammation. Emollients are substances that help to soften and smooth the skin by filling the gaps between the corneocytes (the cells of the stratum corneum) with lipids and oils. This action helps to restore the ‘brick and mortar’ structure of the stratum corneum, reducing water loss and improving the skin’s ability to retain moisture. Various lipophilic substances act as occlusives, forming a protective layer on the skin surface that further prevents water evaporation. Examples of occlusive emollients include petrolatum, waxes, lanolin, and mineral oil. By minimising transepidermal water loss, emollients directly combat the dryness that exacerbates the symptoms of psoriasis.
In addition to emollients, a comprehensive general skincare routine is essential for managing psoriasis. This routine typically begins with gentle cleansing. Harsh soaps and cleansers containing strong detergents can further strip the skin of its natural oils, worsening dryness and irritation. Synthetic detergent cleansers (syndets) are often recommended as they provide effective cleansing while minimising damage to the skin barrier. Mild cleansing bars can also play a key role in fundamental skincare for individuals with skin diseases. The choice of cleanser should be tailored to the individual’s needs, with lipid-free cleansers being suitable for minimal cleansing needs and syndet bars being preferable for more thorough cleansing while maintaining barrier integrity.
Following cleansing, the application of a moisturiser is a critical step. Moisturisers are formulations designed to add and/or retain water in the stratum corneum. They often contain a combination of emollients to smooth the skin, occlusives to prevent water loss, and humectants to attract and hold moisture within the skin. Humectants such as glycerin, sorbitol, sodium hyaluronate, and urea draw water from the atmosphere and the lower layers of the skin into the stratum corneum, further enhancing hydration. The inclusion of urea in moisturisers is particularly beneficial in psoriasis as it acts as a physiologic humectant and can exert ultrastructural changes in the stratum corneum, hydrating severely compromised skin and supporting barrier function. Film-forming polysaccharide materials like hyaluronic acid can also bind and retain water, helping to keep the skin supple and soft.
The regular and consistent application of emollients and moisturisers is crucial in managing the dryness and scaling associated with psoriasis. By improving skin hydration and restoring the barrier function, these products can help to reduce the appearance of scale, alleviate itching, and decrease the frequency and severity of flares. Some moisturisers can even make scale less visible by altering its refractive index. While general moisturisers recommended for sensitive skin may be popular among dermatologists, it’s important to note that moisturisers specifically formulated for psoriasis may offer targeted benefits, although the fundamental principle remains the restoration of the skin barrier. The National Psoriasis Foundation even suggests that simple and economical options like cooking oils and shortening can be effective alternatives to commercial moisturisers due to their occlusive properties. Furthermore, a general skincare routine for psoriasis should address other factors that can impact skin health. Avoiding very hot water during washing, patting the skin dry instead of rubbing, and protecting the skin from environmental irritants are all important considerations. Maintaining adequate hydration through oral fluid intake can also contribute to overall skin health. In summary, emollients and a consistent, gentle skincare regimen are fundamental to the management of chronic dry skin diseases like psoriasis. By directly addressing the compromised skin barrier and the resulting dryness, these measures can significantly improve the symptoms, prevent exacerbations, and enhance the well-being of individuals living with these conditions.