The blisters associated with dyshidrosis occur most commonly on the sides of the fingers and the palms. Sometimes the soles of the feet also can be affected. The blisters are usually small — about the width of a standard pencil lead — and grouped in clusters, with an appearance similar to tapioca. In more-severe cases, the small blisters may merge to form larger blisters. Skin affected by dyshidrosis can be painful and very itchy. The blisters dry and flake off in about three weeks.  Dyshidrosis tends to recur fairly regularly for months or years.