Treatments for arm rashes will depend on the underlying cause ... It appears as smooth, clearly defined patches on the skin. It looks red on lighter skin but may look gray, purple, or darker ...

Leukemia petechiae is a rash that people with leukemia often experience on their arms, legs, or trunk. Petechiae are tiny ...

"Having a big red splotch on your arm for a couple of days may not be fun, but the reality is there's no need to panic and no reason not to get your second shot." Brown's rash subsided after a few ...

Eczema is a common skin condition, but there are many types of eczema out there. Learn how to identify your rash with these ...

Medically reviewed by Susan Bard, MD An itchy, blister rash can be caused by an allergic reaction; an autoimmune disorder; a ...