As a Trichologist, we recommend certain vitamins & supplements like Biotin, B-Complex, Zinc and Magnesium, these need to be taken after a meal.
I agree she needs blood work for thyroid, hormone levels and her DHT levels.
We all are in a shedding period right now, and we shed twice a year being animals just like cats & dogs, so ask her to gather the hair that is falling out and check it, if they are all longer hairs and no short ones, then many times she's in Telogen stage and what kicks out an old hair is a new one and she should see new hairs popping up in about 3 to 4 months.
I would recommend getting her on Olaplex #3 and then a protein/moisture, after rinsing & shampooing the Olaplex out, I recommend the Redken Extreme Mask, it has the 3 elements she needs, protein, moisture and Ceramides which are the inner-cellular cement that keeps the hair bundles tight together, between the Olaplex for the inner part of the hair and the Redken Extreme Mask for the outer part, you'll be doing all your can for your client.