A skin rash is an area of skin that has become swollen, inflamed, or irritated. Skin rashes can include skin bumps that look like pimples or sores; blotchy, scaly or red skin; and itchy or burning skin. Allergens, heat, and certain medical conditions (some more serious than others) can all cause skin reactions like these. Some skin rashes occur right away, while others take some time to develop. Some tend to occur on the face while others flare up on the arms, legs, or torso. Location, appearance, and color of a skin rash are all factors in determining the right diagnosis and the right treatment. Some rashes may be relatively harmless and easy enough to take care of at home while others can be more problematic.