What are these scales on my eyebrows causing them to fall out? (Photos)

This needs an in-person evaluation. I recommend getting a formal evaluation with a hair loss expert to go over your condition and advise you on best treatment options. Prp and progesterone can be used to regrow eyebrows. See an expert. Best, Dr. Emer

A biopsy might help but is not a 100 % guarantee to give the answer. An eyebrow biopsy also leaves a permanent scar. A careful review of your story and up-close dermatoscopic examination of your scalp and eyebrows (and eyelashes and body hair) will likely yield a diagnosis.

Scales can be caused by psoriasis and other conditions which require a direct examination by a dermatologist