I was diagnosed with alopecia due to taking carbimazole but they changed it to propylthiouracil and my hair stopped falling out pretty quickly it's even grew back in x
hair loss is very worrying - it can be due to several things, some amongst, thyroid disease, adrenal (stress) problems, female hormones estrogen/progesterone.
check out website www.*****.com and www.*****.com - both specialists in thyroid and adrenal - great info on sites. Your wife needs checking for hashimotos which is an autoimmune disease (they test blood for antibodies). If someone has an autoimmune disease, hair loss (alopaecia) can be a sign of a second autoimmune - check out dr david fenton, dermotologist st thomas hospital, london, uk and his article on hair loss.
I would have a variety of thyroid test completed are they just checking her TSH