Nummular dermatitis: Diagnosis and treatment
How do dermatologists diagnose nummular dermatitis?
Dermatologists often diagnose nummular dermatitis by looking at the patient’s skin. During the exam, the dermatologist may swab the sores if the doctor thinks you have a skin infection.
If your dermatologist thinks you have an allergy, patch testing (skin tests to find allergies) may be recommended. Your dermatologist also may recommend patch testing if treatment does not fully clear your skin. An allergy can prevent the skin from clearing.
How do dermatologists treat nummular dermatitis?
These sores can be stubborn, so seeing a dermatologist for treatment is recommended. Treatment for nummular dermatitis consists of the following:
- Protect your skin from getting scraped, cut, or injured in any other way. A skin injury can worsen nummular dermatitis.
- Hydrate your skin. You can do this by taking a 20-minute lukewarm bath or shower once a day. Within 3 minutes of getting out of the water, apply a moisturizer to your still-damp skin. This helps hydrate dry skin. It also relieves the itch and scaling. Adding bath oil to the water also may help. Beware that some oils can irritate your skin. A dermatologist can recommend bath oil that will not irritate your skin.
- Use medicine as directed by your dermatologist. Medicine prescribed to treat the skin includes corticosteroid ointments and tar creams. These help reduce inflammation (redness and swelling) and itch. If a bacterial skin infection occurs, your dermatologist will prescribe an antibiotic. An oral (by mouth) antihistamine that makes you drowsy can help you sleep.
If you have a bad case or widespread nummular dermatitis, you may need:
- Medicated dressings (bandages).
- Phototherapy (treatment with light).
- Oral antibiotics.
- Systemic (taken by mouth or injected) corticosteroids.
- Bed rest in a cool and moist room. You can keep the room moist with a humidifier.
With proper treatment, nummular dermatitis can clear completely. Sores on the thighs, legs, and feet often take longer to heal and tend to leave behind darker or lighter spots.
Some patients’ skin clears within a year. Others have these patches for many years. Sometimes the patches go away and then return. Patches that return after clearing tend to appear in the same place as the first outbreak.