Dermatitis is a common condition that causes irritation, redness and swelling of the skin. It often manifests as a rash that is dry and itchy but it can cause the skin to blister, weep and flake. Dermatitis can have a variety of causes in the foot ranging from bacterial or viral infections to auto-immune or allergic. This is why its important to have any foot rash evaluated by a provider. In most cases dermatitis can be treated with prescription creams. Dermatitis is not contagious.