Eczema types: Nummular eczema signs & symptoms
Where does nummular eczema develop on the body?
This type of eczema usually develops on the legs, forearms, or backs of the hands — and often on both sides.
What are the signs and symptoms of nummular eczema?
If you have nummular eczema, here are the signs and symptoms that can develop. The following pictures show what you may see on your skin.
Tiny bumps and blister-like sores
The is often the first sign. The tiny bumps and blister-like sores may appear after you injure your skin. For example, a scrape on the back of one knee could trigger nummular eczema bumps on the backs of both knees.
Coin-shaped raised spots
The tiny bumps will crust over and join together. This causes the coin-shaped spots that this type of eczema was named for. Nummular means resembling a coin, and these round to oval-shaped spots can look like imperfectly shaped coins.
Spot color varies with skin tone
If you have a darker skin tone, you may see brown spots. The spots can also appear lighter than your natural skin color. On lighter skin tones, the spots are pink or red. Regardless of color, these raised (and often scaly) spots can last for weeks or months.
Itchy, extremely dry skin
The spots can be intensely itchy. This itch tends to worsen when you relax or try to sleep. Some people say the skin with nummular eczema burns or stings. The skin between the spots is often extremely dry.
Infection
Scratching the intensely itchy spots can cause raw, open skin. If germs from your hands spread to the open and raw skin, you may develop an infection. Signs of an infection include yellow or golden crusts on the spots of nummular eczema.
If you develop an infection, get immediate medical care.
An infection can start on skin with or without nummular eczema. Look for yellow or golden crusts, streaks of red (light skin) or brown (dark skin), swelling, or pus. Infected areas may feel tender or painful.
Spots flatten
As the spots start to clear, they flatten out. The center of the spot may clear first, as shown here.
Flat dark spots
After a spot clears, you may see a flat spot of discolored skin. The flat spot that appears when nummular eczema clears is a skin reaction. It’s not nummular eczema. Most people who develop skin discoloration have darker skin tones.
New flare-ups
Some people continue to get nummular eczema. When this happens, new spots may appear as older ones clear or time may pass before the next flare-up. If flare-ups continue, you tend to see large, raised patches instead of coin-shaped spots.
Why some people continue to develop nummular eczema isn’t entirely clear. Researchers have learned that some people have a higher risk of developing this type of eczema. To find out if you’re at risk, go to: Nummular eczema: Causes.
Images
Images 1-4 and 6: Used with permission of DermNet NZ.
Images 5 and 7: Getty Images
Image 8: Used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides.
References
Jiamton S, Tangjaturonrusamee C, et al. “Clinical features and aggravating factors in nummular eczema in Thais.” Asian Pac J Allergy Immunol. 2013;31(1):36-42.
Leung AKC, Lam JM, et al. “Nummular eczema: An updated review.” Recent Pat Inflamm Allergy Drug Discov. 2020 Aug 10. [online ahead of print].
Miller JL, “Nummular dermatitis (nummular eczema).” In James WD [editor]. Medscape. Last updated November 2020.
Purnamawati S, Indrastuti N, et al. “The role of moisturizers in addressing various kinds of dermatitis: A review. Clin Med Res. 2017;15(3-4):75-87.
Reider N, Fritsch PO. “Other eczematour erupution.” In: Bolognia JL, et al. Dermatology. (fourth edition). Mosby Elsevier, China, 2018:233-4.
Trayes KP, Savage K, et al. “Annular lesions: Diagnosis and treatment. Am Fam Physician. 2018 Sep 1;98(5):283-91.
Written by:
Paula Ludmann, MS
Reviewed by:
Erin Ducharme, MD, FAAD
Amanda Friedrichs, MD, FAAD
Last updated: 3/15/21