How to Tell the Difference Between Nummular Eczema and Ringworm
It’s often difficult to distinguish between nummular eczema and ringworm, so it’s always best to be evaluated by a dermatologist, say experts.
Published On: Nov 1, 2016
Last Updated On: Feb 1, 2024
Plunging temperatures signal it’s time to pull out the cozy knitwear and gather around the fireplace (or space heater) on chillier nights. But, for people with eczema, winter also heralds a season of drier, more sensitive skin. Lower humidity, icy wind and indoor heating can all sap much-needed moisture from your skin.
We spoke with Dr. Smita Aggarwal, board-certified dermatologist and pediatric dermatologist at Medical Dermatology Associates of Chicago, about foolproof ways to keep your skin calm during winter.
Your skin forms a protective barrier against bacteria, germs and other environmental invaders. However, eczema can cause this barrier to weaken, as can harsh winds and winter elements.
“To keep [your skin barrier] strong, it needs moisture regularly to prevent irritants and allergens from entering,” said Dr. Aggarwal. “Moisturizers with a higher oil content, such as ointments, and specialized ingredients, such as ceramides, are especially helpful in repairing skin that has lost its water and lipid content.”
Oil-based moisturizers help protect against moisture loss through the skin barrier, and ointments are especially beneficial to help lock in moisture when humidity falls.1 However, try not to use ointments on areas that may get hot and sweaty, as it may cause further irritation. Ointments form a layer that can block your pores and prevent sweat from leaving the body. Instead, sweat accumulates on the skin which, when mixed with the ointment and other external debris, can lead to irritation and itching.2
While reaching for a thicker cream or moisturizer is crucial during a cold snap, timing is of the essence. Dr. Aggarwal recommended applying moisturizer and/or ointment to your skin at least twice a day. And, before you go outside, make sure to apply a thick layer of moisturizer to any exposed areas of skin. “Apply thicker ointments to areas of the skin which are exposed to the elements, such as the face and hands, before venturing outdoors and rehydrate these areas at bedtime,” said Dr. Aggarwal.
“Humidifiers can be very helpful in alleviating symptoms of eczema in the winter,” said Dr. Aggarwal. “During these cooler months, the air inside our homes is already dry due to the weather, and then becomes even more dry as we turn our heat on around the clock. Our skin suffers as a result.”
When our skin cannot take in moisture from our environment, the more dry and cracked it can become. To help replenish your skin’s moisture, Dr. Aggarwal recommended running a humidifier when you go to bed or during the day if you spend significant time at home.
You may need to experiment to find the right humidity level to help soothe your skin. There are some types of eczema that flare with excess humidity. It’s important to pay attention to how your skin reacts when you have the humidifier on in the winter.
For some people with eczema, they find their skin actually does better during the wintertime. In these instances, the summer months can be more problematic. The summer heat, sweat and humidity can trigger more eczema flares.3
Whether a humidifier helps or exacerbates your eczema during the winter, it is a good reminder that there isn’t one type of eczema experience, Dr. Aggarwal noted. Your skin is unique, and what works for someone else may not work for you.
Pay most attention to the fabric closest to your skin before you layer up and go outside. “For the base layer, I always recommend 100% cotton, ideally organic, to minimize your exposure to allergens in clothing,” Dr. Aggarwal said. Layering your outerwear also lets you remove layers as you warm up to help prevent overheating. People with eczema can flare if they overheat, so breathable fabrics like cotton allow for better airflow to keep the skin cool.
Your third or fourth layer of clothing may not touch your skin, but Dr. Aggarwal still recommended avoiding wool because it can be quite itchy for people with eczema.4 You should also avoid wool in winter accessories like scarves and gloves.
For winter gloves, it is best to wear gloves that are 100% cotton or made of a breathable material that does not cause your hands to overheat. If you’re concerned cotton gloves may not provide sufficient warmth, you can try wearing a thin, cotton glove next to your skin and then layering a different glove over it for extra protection.
Whether you got wet socks from playing in the snow or a sweaty undershirt after walking home in warm layers, the winter elements can leave you with damp clothing. When you go indoors to warm up, make sure to shed your wet clothes and shoes immediately. Wet clothes next to the skin can cause irritation and a flare if worn for too long.
Sunscreen gets the most attention during summertime but it is just as necessary when the temperature drops. The sun’s reflective powers remain just as strong during winter and can even be magnified when it snows or you head up to the mountains.
Before going outside into the cold, apply a heavy layer of moisturizing, broad-spectrum sunscreen with an SPF of 15 or higher to your face, hands and other exposed skin. Broad-spectrum sunscreen provides extra skin protection from both types of the sun’s rays (UVA and UVB). Several products also combine oil-based moisturizing creams with sunscreen for double the moisture and protection.
References:
1. Purnamawati S, Indrastuti N, Danarti R, Saefudin T. The role of moisturizers in addressing various kinds of dermatitis: A review. Clin Med Res. 2017;15(3-4):75-87. doi:10.3121/cmr.2017.1363
2. Murota H, Yamaga K, Ono E, Murayama N, Yokozeki H, Katayama I. Why does sweat lead to the development of itch in atopic dermatitis?. Exp Dermatol. 2019 Dec;28(12):1416-1421. doi: 10.1111/exd.13981
3. Sargen MR, Hoffstad O, Margolis DJ. Warm, humid, and high sun exposure climates are associated with poorly controlled eczema: PEER (Pediatric Eczema Elective Registry) cohort, 2004-2012 [published correction appears in J Invest Dermatol. 2014 Jun;134(6):1779]. J Invest Dermatol. 2014;134(1):51-57. doi:10.1038/jid.2013.274
4. Jaros J, Wilson C, Shi VY. Fabric selection in atopic dermatitis: An evidence-based review. Am J Clin Dermatol. 2020;21(4):467-482. doi:10.1007/s40257-020-00516-0
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