Occasionally, people with skin complaints like eczema are advised by well-meaning friends and family to “dry it out.” They may be advised to apply drying astringents, spend time in the sun, and avoid moisturizing the skin until the eczema “dries up” and passes.
This is an extraordinarily bad idea that could actually worsen your symptoms and prolong your flare. This is where a little knowledge of how eczema develops can help you out.
Eczema: A Disorder of the Skin Barrier
There is no single “cause” for eczema; the skin disorders that share this name arise, instead, from a combination of factors ranging from genetic predisposition to environmental influences.
One constant thread connects all cases of eczema, though–it involves a compromised skin barrier.
What is your skin barrier?
Your “skin barrier” refers to the combination of skin cells, proteins, fatty acids, and lipids that make up the stratum corneum, or the outermost layer of your epidermis. It consists of flattened, somewhat squarish skin cells called keratinocytes arranged in a pattern similar to the shingles on a roof.
Keratinocytes also secrete lamellar bodies, organelles full of lipids, fatty acids, proteins, and amino acids. Once the lamellar bodies are secreted, the keratinocytes are no longer living cells; they are almost pure keratin that exists to protect the maturing cells beneath them.
The lamellar bodies contain lipids like waxy ceramides, as well as proteins. Keratinocytes produce and secrete a tough, fibrous protein called keratin. Ceramides and keratin fill in the extracellular spaces between the keratinocytes. They function as a glue to hold the cells together.
Keratinocytes also secrete filaggrin, another protein that fills in the extracellular spaces of the stratum corneum. There, it breaks down, leaving behind urea, amino acids, and fatty acids as it does. These are all part of the NMF natural moisturizing factor that keeps your skin soft and hydrated.
Chemical and Physical Defenses
All together, the interlocking keratinocytes, their lamellar bodies, and the lipids and proteins they secrete make up your skin barrier. This barrier keeps foreign irritants and diseases away from the delicate tissues and developing cells beneath the stratum corneum. It prevents moisture from evaporating from the skin cells, and it also prevents external water molecules from infiltrating cells and water logging them.
The compounds in the NMF soften the skin cells and draw water into the stratum corneum to keep the cells plump and healthy. They also have antimicrobial properties that protect your skin from infection, in addition to creating a harmonious microbiome.
Your microbiome is a sort of community of microbial organisms. When the microbiome is balanced, these helpful microbes outnumber disease-causing fungi and bacteria.
Why is your skin barrier important?
Your skin isn’t just a nice veneer over your organs and muscles; it is your body’s biggest organ by weight and by area. It plays a vital role in protecting you from disease and maintaining homeostasis, a state of optimal function and adaptation to the environment.
Your first defense…
Your skin barrier is your first defense against harmful substances in the environment. It acts as a look-out for your immune system, often signaling for immune cells when a pathogen is introduced to the body.
It protects your body’s vulnerable tissues from UV radiation, which causes cellular death and damages DNA. Eczema is a sign that this very important barrier has become compromised.
Eczema: What It Is
Eczema is a sign that your skin barrier is not functioning properly. It’s characterized by transepidermal water loss (TEWL) and inflammation. As the flare progresses, skin becomes increasingly dry.
When your skin barrier is disrupted, irritants can easily breach the skin. Remember, your skin acts as a look-out for external threats. When immune cells in your skin recognize such a threat, they send up an alarm that summons a number of other immune cells.
These cells perform a variety of tasks. Some of them dilate your blood vessels so blood can flow to areas that are injured. Others act to surround the offending particles and flush them out.
The external signs of all this activity include redness, itch, swelling, and rash.
When your skin barrier is compromised, the microbiome can quickly become unbalanced. This is called dysbiosis. Yeasts such as Malassezia and bacteria such as staphylococcus aureus (Staph A, or simply “staph”) reproduce rapidly and overpopulate the microbiome.
These microbes act as superantigens and trigger inflammation, setting eczema flares off or aggravating them. Staph is commonly found on biopsies of skin affected by eczema. First these pathogens cause over-colonization. Sometimes, these pathogens cause true infection.
When eczema lesions become infected, it’s called infected eczema. Infected eczema is uncomfortable, often painful. It can also lead to infection in deeper layers of your skin or the subcutaneous tissues, which is potentially dangerous. It can also lead to painful infections with the HSV Herpes virus, called eczema herpeticum.
What eczema isn’t
Eczema can cause oozing when it’s acute, and this requires gentle cleansing before applying topical therapy and absorbent cotton dressings. But eczema is not the result of excessive moisture; in fact, accelerated TEWL is a prominent characteristic of flares. Additionally, flares are often triggered by dry skin.
Dry skin is less hospitable to beneficial microbes. It is more prone to damage, which opens the skin up to irritation and infection. All of this increases the risk of flares.
“I have weeping eczema, though”
As eczema flares progress, small, fluid-filled blisters may form in the epidermis. They may swell and ooze a clear or straw-colored fluid.
This is not a sign that the skin is producing too much moisture. To the contrary, it signifies that inflammation is active and progressing. It occurs because inflammation dilates the blood vessels, which thenleak serum–a clear, protein-rich fluid–into the soft tissue of the skin. This leads to swelling (edema) of the skin and oozing of the serum. Acute raw red skin can also directly weep serum without blisters forming.
As this inflammation worsens, the skin is prone to painful fissures, which leaves it open to opportunistic infection.
Infection can cause weeping, as well. Staph is the most common pathogen found in infected eczema; it often results in a yellowish or pus-like discharge. Certain types of staph bacteria can cause superficial peeling blisters to occur through a toxin effect. Another pathogen that commonly infects eczema lesions is the herpes simplex virus (HSV-1), spreading from a cold sore. This causes a painful crusting scabbing condition called eczema herpeticum, and often affects infants and children. Oral or even IV intravenous antibiotic Acyclovir is required in addition to eczema topical care and infection precautions.
If your eczema rash is weeping, “drying it out” is not the answer. Instead, you should see a doctor to rule out infection, which sometimes requires antibiotics. Your doctor will also help you get the inflammation under control; this will allow the dilated blood vessels to return to normal. Swelling will go down, and serum will no longer weep.
Moisture heals eczema
Moisture loss and dryness are warning signs of poor barrier function that can lead to subacute and acute dermatitis. Remember the NMF, the natural moisturizing factor? It plays a significant role in keeping your skin healthy. Many people do not produce adequate NMF because of a mutation on the gene responsible for filaggrin synthesis. These people are more likely to develop eczema.
Drying the skin even further is not the answer to eczema flares–quite the opposite. Regular moisturization is the foundation of eczema prevention. Moisturizing twice daily is imperative; during active flares, the skin benefits from even more frequent applications.
What kind of moisturizer should I choose?
Moisturizers come in a wide variety of formulations. Some are lightweight lotions, some are creams. Others are tinted to even out skin tone. Still others are thick ointments that are heavier, even, than creams. Which one is right for you?
Ingredients in moisturizers
Most moisturizers utilize more than one of these ingredients; some ingredients, like glycerin, manage all three roles.
- Occlusives are heavy lipids that sit on the skin’s surface and prevent water from evaporating from the surface of the skin. Occlusives by themselves tend to have a thick, greasy consistency.
Petrolatum (petroleum jelly or VaselineⓇ), beeswax, mineral oil, and dimethicone are all examples of occlusives. Mink oil, emu oil, and lanolin are some others.
Some common humectant ingredients in moisturizers include:
- urea, a component of the NMF. Urea improves absorption of water into the stratum corneum and promotes the shedding of dead skin cells. It also helps topical medications penetrate the skin more efficiently.
Urea reduces and improves itching, making it a useful ingredient for people with eczema, hyperkeratosis, and other drying skin disorders.
- Alpha-hydroxy acids (AHAs), including glycolic and lactic acids. These ingredients affect the hydration of the stratum corneum in a variety of ways: attracting water molecules, encouraging dead skin cells to shed, and increasing levels of ceramides. They cause stinging and irritation for active eczema.
- Glycerin is a common ingredient in skincare products. It attracts and binds water and helps repair the skin barrier. Other humectants include honey, propylene glycol, sorbitol, and hyaluronic acid
Some ingredients manage all three roles at once, making them useful for a wide variety of skincare needs. Glycerin, for example, is a powerhouse that acts as a humectant, emollient, and humectant at once; it has been shown to have antimicrobial properties.
The Science of Moisturization
People sometimes speak about choosing a moisturizer as a question of choosing whether they need a humectant, an occlusive, or an emollient. In reality, it is not that simple.
It seems intuitive to add a humectant to dry skin. However, if the air is not adequately humid, the humectant can actually contribute to TEWL. They should be used with an occlusive or an emollient.
Similarly, in the absence of a topical humectant, an occlusive adds no moisture to the skin. It would prevent TEWL, but this is a moot point if there is not enough water in the cells to begin with. As water migrates to the epidermis from deeper levels of skin, dryness would improve–but this process takes days.
The solution is in finding a product that addresses all of your skin’s specific needs. If you are prone to oily skin and acne, then a lotion containing a humectant and a lightweight emollient is probably your best bet.
If your skin is dry, a heavier lotion with more humectants and strong occlusive (like petrolatum) is probably better. Ointments usually work better than everyday creams or lotions for those with active eczema flares.
Is There a Single Product That Does It All?
More and more, people are turning towards moisturizing systems that incorporate multiple products, including hydrating serums, moisturizing creams, and oils. Some find it beneficial to use different products for day and nighttime use like an eczema cream and moisturizer.
It’s not easy to find a grab-and-go solution to moisturization; if you’re prone to eczema flares, you will probably need more intense hydration during those flares than you usually do. However, some products are formulated to address a multitude of needs, including hydration, TEWL prevention, and softening.
A strong contender would be HarlanMD Perfect Repair™ moisturizing cream, which was formulated by board-certified dermatologist Dr. Steve Harlan for people with complicated moisturization needs.
Perfect Repair™ is loaded with natural ceramides. It also contains coconut oil for its powerful healing benefits and occlusive properties. It ticks off all the boxes, containing several humectants, emollients, and occlusives. It also leverages prebiotics to keep the skin’s microbiome balanced.
If you’re looking for a do-it-all moisturizer, read the labels carefully. Check the ingredients against the list above to see if it offers a well-rounded complement of properties. Keep in mind that the ingredients listed first will be those that constitute the bulk of the product’s volume, continuing in descending order. Also look out for fragrances, dyes, and emulsifiers that can irritate your skin.
“Drying out” your eczema is not advisable. It will not be effective, and it can further damage your skin barrier.
If you are experiencing weeping, or oozing–or if you notice crusts where fluid has dried over the skin– gently cleanse with water and a hydrating cleanser before applying ice and topical therapy. Before using moisturizer, spritz the skin with water and be ready to apply ice for 2 minutes for acute and subacute dermatitis stinging. Some patients must start with a small amount of Vaseline Petrolatum aka white petrolatum. With improvement, apply your moisturizer more frequently and avoid the Petrolatum, making sure to apply it in a thin streaky layer. Follow your prescription plan, and consider adding an eczema cream such as SmartLotionⓇ to address inflammation without risking topical steroid withdrawal or atrophy.
If weeping persists, and the skin is warm, see your doctor as soon as possible. It’s important to have any infections quickly diagnosed and treated. Follow with a dermatology provider for supervision and guidance with topical corticosteroids.
Avoid excessive sunlight, and avoid chronic use of tanning beds.
During eczema flares, your skin is crying out for more supportive care. It doesn’t deserve the damage and inflammation “drying out” your eczema will cause–and you deserve relief from your eczema symptoms. Some extra care and moisturization will get you closer to that relief.