I have alopecia areata and see many short hairs on my scalp and wonder if they are exclamation mark hair or regrowing hairs. How can I tell?
It's generally quite easy to tell an exclamation mark hair from a regrowing hair. A regrowing hair is thick at the bottom and 'pointy' at the top. Regrowth gets longer and longer over time. In contrast, an exclamation mark hair is wider at the top and thinner at the bottom where it enters the scalp. The exclamation hair does not get longer and longer over time. In fact, it usually falls out of the scalp.
You may wish to review these helpful articles (below) I've written in the past. Thanks again for the question.