my son is 1 year old and he is having some kind of rashes or allergy on his legs..what is it?what is the remedy doctor?

A. hi dear Allergic contact dermatitis occurs when the skin comes into direct contact with an allergen. The result of the skin allergy is a red, itchy rash that can include small blisters or bumps. The rash arises whenever the skin comes into contact with the allergen, a substance that the immune system attacks.