I have a red area on my leg?

Dermatitis: Redness of the skin without associated pain, itching , swelling, bumps or drainage is likely inflammation such as eczema. Could be a reaction to something that touched the skin. If any symptoms such as those listed are present this could suggest an internal problem such as blocked arteries or vein valve leakage, rather than a simple skin irritation. Eczema gets better w/cortisone cream.