The characteristic symptom of alopecia areata is the sudden onset of round or oval-shaped patches of hair loss on the scalp, although it can also affect other areas of the body, such as the eyebrows, eyelashes, and beard. In some cases, the hair loss may progress to involve the entire scalp (alopecia totalis) or the entire body (alopecia universalis). The affected areas of the skin are usually smooth and devoid of any signs of inflammation or scarring.