(See also Overview of Dermatitis.)
Hand and foot dermatitis often first starts as small blisters (called dyshidrotic dermatitis). This is a misnomer, however, because dyshidrotic means caused by abnormal sweating, but hand and foot dermatitis has nothing to do with sweating or abnormal sweat glands.
Frequent or prolonged water contact (for example, frequent handwashing or work involving water or wet substances), particularly with detergents, is a common trigger, particularly in people who have atopic dermatitis, hay fever, and asthma (a combination called atopy).
The most severe form of dyshidrotic dermatitis is called pompholyx. Pompholyx is characterized by tiny blisters that come together to form larger blisters.
Symptoms of hand and foot dermatitis include redness, scaling, and thickening of the skin on the hands and feet. These symptoms may progress to itchy small blisters or large blisters on the palms, sides of the fingers, or soles. These blisters can rupture, resulting in oozing and crusting. The blisters may be the first symptom people notice. Symptoms can come and go. The skin can become infected (for example, by bacteria or fungi).
If a cause is known, it is treated.
People should avoid contact allergens as well as skin irritants, particularly frequent or prolonged contact with water and detergents.
Corticosteroids applied to the skin are sometimes given to relieve inflammation. Antihistamines can help relieve itching.
Phototherapy (exposure to ultraviolet light), sometimes preceded by soaking in a psoralen solution before exposure, can help.
For severe hand and foot dermatitis, corticosteroids can be taken by mouth or sometimes can be injected but preferably are used for only a short term. Occasionally, if long-term immunosuppressive treatment is required, cyclosporine, mycophenolate, or methotrexate can be given by injection.
Infections are treated, typically with antibiotics.