What factors exacerbate eczema?

Individuals with eczema have a fragile skin barrier and hydrolipidic film, and often experience significant dryness, known as xerosis, between eczema flare-ups. This hydrolipidic film plays a crucial role in skin protection and limits the penetration of allergens. To combat skin dryness and strengthen this film, it is recommended for those suffering from eczema to apply a emollient balmdaily, which has moisturizing and protective properties.

Sweating can be a source of skin irritation, especially in areas with eczema lesions. Indeed, it can cause burns or tingling sensations. This is largely due to the natural acidity of sweat, which has a pH between 4 and 6. Additionally, it contains sodium chloride, or salt, which has a drying effect on the skin. Dry skin, in turn, is a factor that exacerbates eczema. That's why it's recommended for people suffering from eczema to take a quick shower immediately after physical activity, followed by the application of an emollient.

Stress has a very negative effect on most skin diseases, including eczema. Several biological mechanisms are at work, among which is the degranulation of mast cells, immune cells involved in allergic reactions. This is mediated by neuropeptides released by cutaneous nerve fibers: CRH (Corticotropin Releasing Hormone), neurotensin, substance P, and other tachykinins. The release of these hormones triggers a cascade of reactions leading to the release of mediators responsible for the itchiness of eczema and the dilation of blood vessels.

It has been demonstrated that colonization by certain parasites can exacerbate eczema. A recent study highlighted in a murine model mimicking a case of dermatitis that fungi of the genus Malassezia could trigger an increased release of interleukins 17 and 23 (IL-17 and IL-23). These cytokines, in turn, worsen eczema and skin inflammations more generally.

Eczema often becomes more severe in winter. Indeed, the cold air during this time of the year tends to cause dryness and skin irritations, which are factors that exacerbate eczema. Therefore, it is advisable to dress warmly in winter and to use gloves, as hands are often the first victims of the winter cold. We also recommend using a nourishing hand cream during winter, and reapplying as often as you feel the need.

Several studies have shown that there is a link between pollution and the worsening of eczema. It has been specifically proven that exposure to fine diesel particles can increase itching in children suffering from eczema. Moreover, air pollution can also trigger an increase in the production of free radicals in the body, species that cause cellular damage and exacerbate skin inflammation.

Smoking is an exacerbating factor for eczema due to the irritating and polluting substances that a cigarette contains. These compounds easily penetrate the fragile skin barrier of atopic skins and trigger immune responses that cause eczema flare-ups. Moreover, it is estimated that a puff of cigarette smoke releases 200,000 free radicals. Thus, whether active or passive, smoking is currently considered the primary exacerbating factor for eczema.