|Classification and external resources|
Nummular dermatitis (also known as "Discoid eczema," "Microbial eczema," "Nummular eczema," and "Nummular neurodermatitis":82) is one of the many forms of dermatitis. Also known as discoid dermatitis, it is characterized by round or oval-shaped itchy lesions. (The name comes from the Latin word "nummus," which means "coin.")
The disorder is recurrent and chronic, and may appear at any age, although it is most common in people in their 60's. Nummular dermatitis does not appear to be a genetic condition, is not related to food allergies, and is not contagious.
The coin-shaped patches can affect any part of the body, but the legs and buttocks are the most common areas. Flare-ups are associated with dry skin, so the winter season is a particularly bad time for those with this condition.
Other forms of dermatitis are at risk of developing.
Other causes 
Nummular eczema can also be worsened by stress and excessive caffeine, which dehydrates the body and thus the skin.
One of the keys to treatment and prevention involves keeping the skin moisturized. Lotions, creams, and bath oils may help prevent an outbreak. If the condition flares up, a common treatment involves the application of topical corticosteroids. Oral antihistamines may help lessen itching. More severe cases sometimes respond to ultraviolet light treatment.
See also 
- Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. ISBN 1-4160-2999-0.
- James, William; Berger, Timothy; Elston, Dirk (2005). Andrews' Diseases of the Skin: Clinical Dermatology. (10th ed.). Saunders. ISBN 0-7216-2921-0.
- Krupa Shankar DS, Shrestha S (2005). "Relevance of patch testing in patients with nummular dermatitis". Indian journal of dermatology, venereology and leprology 71 (6): 406–8. doi:10.4103/0378-6323.18945. PMID 16394482.
- http://www.dermnet.com/Eczema-Nummular/ - Photo gallery on dermnet.com