Discoid eczema is a type of dermatitis, or skin disease, that is characterized by skin rashes on the affected part of the body. It is not infectious and is not the result of allergy. It can occur at any age and can affect any part of the body. Discoid eczema is also known as nummular eczema and nummular dermatitis.
The main symptom of discoid eczema is skin rashes that develop on the affected part of the body. Although this type of dermatitis can occur anywhere, it is more likely to affect the lower legs. One or several patches can develop at the same time. They tend to be round or oval in shape, and of variable size. The lesions might be as small as a few millimeters in diameter, or might cover an area of 3 inches (7.5 cm) or more.
Most lesions are pale or bright pink in color but might also appear brown or red. Some lesions are very itchy, or the skin around the lesions might be dry, irritable and prone to inflammation. These lesions often clear up without leaving any scars. In some people, however, the lesions might persist for months or even years. Sometimes, the lesions can cause permanent scarring or skin discoloration.
This type of dermatitis generally is not caused by the use of cosmetic products but can be exacerbated by any products that dry out the skin. It often can be triggered by a small burn, an insect bite or another type of minor skin injury. Skin irritation caused by dry, cold weather also can cause this type of dermatitis in people who are susceptible.
Discoid eczema can disfigure the skin, so one of the most important considerations of treatment is in protecting the skin from permanent damage. Taking care of the skin after a minor injury such as an insect sting, an insect bite or a burn can help prevent this type of dermatitis from developing. This is especially important for people who are susceptible.
When patches of discoid eczema do develop on the skin, certain types of over-the-counter medications can help relieve itching and other symptoms. These include oral antihistamines and anti-inflammatory pills or creams. Skin can be further protected with the use of moisturizing creams, bath oils and other skin products that help keep the skin moisturized. Soaps that dry out the skin should be avoided, because these can irritate the skin and worsen itching. Lanolin and glycerin-based creams are particularly useful.
When these home treatments don’t help, prescription medications such as topical steroid creams can help reduce inflammation and skin irritation. If the skin is weeping or crusted, oral antibiotics might be necessary to ensure that no infection occurs. In very severe cases of long duration, ultraviolet light therapy is very effective. This treatment involves exposing the affected area of skin to ultraviolet light several times a week. It can take several months to clear up the dermatitis using this method, but it is an effective and long-lasting treatment.