Maintaining your skin's moisture level is very important if you're prone to eczema. In fact, the Australasian Society of Clinical Immunology and Allergy (ASCIA) says:
“[keeping] skin prone to eczema well hydrated with regular moisturising… is the most important single thing anyone with eczema can do”
But why? Frequent moisturising helps replace moisture that may be lost through the defective lipid matrix (see The differences in eczema-prone skin for more on the lipid matrix). Eczema-prone skin is deficient in some of the vital components that help lock moisture into the skin.2 This leads to moisture constantly being lost, and if it isn’t replenished then you can wind up with dry, dehydrated skin that's susceptible to environmental irritants working their way inside.3
ASCIA recommends moisturising 2-3 times a day, and after every bath or shower.1 This is especially important if you spend a lot of time in dry or hot conditions (like in the air-con at your office or outside in the sun). Also, if water is left on your skin after bathing or showering and then it evaporates, some of the moisture within your skin can be lost.4,5 To prevent this, moisturising immediately afterwards is recommended to help preserve the moisture in your skin.1
To find the best way to maintain your skin's hydration, talk to your dermatologist, GP or pharmacist. They can work with you to figure out how to manage your eczema-prone skin.
It may help you to learn more about some key components of your skin like ceramides, so you can understand what's happening and how to manage it.