Alopecia areata: What is meant by "well demarcated"?

Alopecia areata: Classically well demarcated hair loss


Alopecia areata is an autoimmune condition that affects 1.7 % of the world. Affected patient often develop well-demarcated round or oval-shaped patches of hair loss. The term "well demarcated" means that one can often draw an imaginary line around the area of hair loss as opposed to other hair loss conditions like androgenetic alopecia where is can be challenging to determine where the hair loss starts and ends.

If one looks up close at a typical early staged patch of alopecia areata, a number of findings are often present including:

(1) thin hairs or white hairs within the patch of hair loss and

(2) “exclamation mark” hairs around the perimeter of the patch of hair loss.

Other findings are also present. Spontaneous growth can occur in many patients. However as the size of the patch increases amd as the number of these patches increases, the chance of spontaneous regrowth diminishes. The most effective treatments for a single patch such as the one shown are topical steroids and steroid injections. I frequently add minoxidil if the patch is slower to respond to treatment.

Dr. Jeff Donovan is a Canadian and US board certified dermatologist specializing exclusively in hair loss. To schedule a consultation, please call the Whistler office at 604.283.1887

Share This