Several types of dermatitis can have differing levels of severity and causes, states Mayo Clinic. The most common type is called contact dermatitis and is usually caused by exposure to irritants or allergens, such as poison ivy, perfume, certain kinds of cleaners, or nickel contained in jewelry.
Another common form of dermatitis is atopic dermatitis, explains Mayo Clinic. This type of dermatitis could be caused by a number of specific factors, such as dry skin, bacteria on the skin, or environmental conditions. It may also be caused by variances in one's genes or the immune system not functioning properly. The last type of dermatitis is seborrheic dermatitis. This type is usually caused by a yeast or fungus that infects the oil secretions on a person's skin. The condition may come and go with specific seasons.
Many types of dermatitis can be treated by using corticosteroid creams, according to Mayo Clinic. Some creams may also contain calcineurin inhibitors, which can help certain kinds of dermatitis by affecting the immune system. Another type of treatment is called phototherapy, in which the patient exposes the affected part of the skin or body to controlled amounts of light. The light can either be natural or artificially created.